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#16
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Sata cabling
It's was deemed a less expensive solution at the time.
I have PATA 80 wire for ATA 100 and ATA 133 drives (connected using either round PATA cables or the traditional flat ribbon) plus SATA I and SATA II drives. Don't get me wrong, I'm not against SATA but they just don't deliver on the advertized speed. Plus the connector design of SATA does not give me confidence in constantly connecting Hard Drives on my "Test" computers. -- JS http://www.pagestart.com "Gerry" wrote in message ... JS If pata is faster than sata why has sata replaced pata? BTW I have Sata II -- Gerry ~~~~ FCA Stourport, England Enquire, plan and execute ~~~~~~~~~~~~~~~~~~~ "JS" @ wrote in message ... Well, in a crude sense think of SATA as a two lane highway compared to PATA as an 8 lane highway. If the PATA cable design was updated to handle higher transfer rates I would think that PATA could be at least 4x faster than SATA. And an updated PATA cable need not be a giant size ribbon cable either. Just imagine if your ram memory was serial access instead of DDR2 or DDR3. -- JS http://www.pagestart.com "Gerry" wrote in message ... JS Interesting. Statistically how do data transfer rates compare? -- Gerry ~~~~ FCA Stourport, England Enquire, plan and execute ~~~~~~~~~~~~~~~~~~~ JS wrote: Not crazy over the SATA connectors either. SATA or Serial ATA has another design flaw in that by nature serial data transfers can never be as fast as parallel. "Gerry" wrote in message ... I have had a disk connection problem which seems to relate to failing sata cables. The BIOS has failed intermittently to detect one or both hard drives. The problem was more obvious with the master drive so I replaced the cable 14 days ago and there was no further problem until this morning. The problem this morning was the slave drive so I have replaced the cable for that drive. It has now been working for a bit over two hour. The problem first became apparent a month ago when I found the system would freeze after it had been running some time. Resetting sometimes worked and sometimes resulted in a failed boot. Eventually the system would boot but the problem would happen again some hours later or the next day. Sometimes there have been Event Viewer reports -mainly ID: 11 referring to the Controller. Often the problem is unreported. This is probably because the Error is occurring before Event Viewer starts. From a friend I got these comments. "In my view, the SATA 'Connector' is an engineering blunder. A sort-of flat sleeve slides over a notched part on the edge of the board whereupon sit some exposed/un-insulated traces. Flat conductors encased within a plastic bit are slid into contact with them. There is no mechanism but friction to keep the 'connector' in place. Entirely inadequate. It is not designed for repeated make/break insertion/removal. If subjected even to a low number of such operations (design spec is 50), it will fail. (5 000 for an eSATA connector). If I have to repeatedly disconnect-connect a drive during testing, I replace the cable as a matter of routine." I am interested in knowing whether others have encountered this problem and how common place it is? TIA -- Gerry ~~~~ FCA Stourport, England Enquire, plan and execute ~~~~~~~~~~~~~~~~~~~ |
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#17
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Sata cabling
Paul
This is the motherboard http://www.gigabyte.com.tw/Products/...ProductID=1926 -- Gerry ~~~~ FCA Stourport, England Enquire, plan and execute ~~~~~~~~~~~~~~~~~~~ Paul wrote: Gerry wrote: Paul The computer is a desktop with a Gigabyte 915/910 Series motherboard. The two drives are a Seagate and a Maxtor. The cable connectors do not match any illustrated in your links. Both ends are identical and push vertically down onto the motherboard. On one side of each end of the cable is a spring loaded metal plate but I would not say it locks. The cable stays in place. The connectors on this example, don't seem to have a shroud around the body. Just the wafer and some guides. My motherboard has ones like this. My cables are the part that are providing the retention, as the connector on the motherboard is not helping. http://www.gigabyte.com.tw/FileList/...raphic_big.jpg This is a closeup. This one doesn't support a lock latch, or at least, doesn't look like the one I have in mind. http://www.coolgear.com/images/CD011C00A.jpg This connector has a shroud around the outside, and that is where you'd put a feature to support latching. This still isn't the one I saw before. http://www.coolgear.com/images/CD011D03A.jpg This one claims to support a latch. Maybe inside somewhere. Not sure. http://www.satagear.com/CD011D05A_SATA_Connector.html I'm convinced, if it wasn't for the poorly engineered first attempt at a connector, there wouldn't be so many flavors of connectors out there. There is no way to know, when you buy a motherboard, what you'll get. I've even seen motherboards, where connector types are mixed, some with the shroud, and some without. They use it to distinguish Southbridge ports, from the ports connected to a separate RAID controller (they're not sprinkled randomly). And this connector comes with a fastener, to avoid the embarrassment of one of your customers, ripping the connector right out of the motherboard, when removing a cable :-) A good idea. http://www.coolgear.com/images/CD011D04A.jpg I've seen at least one connector with a shroud, where there is a rectangular hole in the shroud, where the lock latch grips onto. I cannot find a picture of it right now. There is a nice collection of pictures here as well. http://cooldrives.stores.yahoo.net/saiandsaiiin.html Paul |
#18
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Sata cabling
JS
The design specification is 50 insertions and removals. The cable dates from December 2005. -- Gerry ~~~~ FCA Stourport, England Enquire, plan and execute ~~~~~~~~~~~~~~~~~~~ JS wrote: It's was deemed a less expensive solution at the time. I have PATA 80 wire for ATA 100 and ATA 133 drives (connected using either round PATA cables or the traditional flat ribbon) plus SATA I and SATA II drives. Don't get me wrong, I'm not against SATA but they just don't deliver on the advertized speed. Plus the connector design of SATA does not give me confidence in constantly connecting Hard Drives on my "Test" computers. "Gerry" wrote in message ... JS If pata is faster than sata why has sata replaced pata? BTW I have Sata II -- Gerry ~~~~ FCA Stourport, England Enquire, plan and execute ~~~~~~~~~~~~~~~~~~~ "JS" @ wrote in message ... Well, in a crude sense think of SATA as a two lane highway compared to PATA as an 8 lane highway. If the PATA cable design was updated to handle higher transfer rates I would think that PATA could be at least 4x faster than SATA. And an updated PATA cable need not be a giant size ribbon cable either. Just imagine if your ram memory was serial access instead of DDR2 or DDR3. -- JS http://www.pagestart.com "Gerry" wrote in message ... JS Interesting. Statistically how do data transfer rates compare? -- Gerry ~~~~ FCA Stourport, England Enquire, plan and execute ~~~~~~~~~~~~~~~~~~~ JS wrote: Not crazy over the SATA connectors either. SATA or Serial ATA has another design flaw in that by nature serial data transfers can never be as fast as parallel. "Gerry" wrote in message ... I have had a disk connection problem which seems to relate to failing sata cables. The BIOS has failed intermittently to detect one or both hard drives. The problem was more obvious with the master drive so I replaced the cable 14 days ago and there was no further problem until this morning. The problem this morning was the slave drive so I have replaced the cable for that drive. It has now been working for a bit over two hour. The problem first became apparent a month ago when I found the system would freeze after it had been running some time. Resetting sometimes worked and sometimes resulted in a failed boot. Eventually the system would boot but the problem would happen again some hours later or the next day. Sometimes there have been Event Viewer reports -mainly ID: 11 referring to the Controller. Often the problem is unreported. This is probably because the Error is occurring before Event Viewer starts. From a friend I got these comments. "In my view, the SATA 'Connector' is an engineering blunder. A sort-of flat sleeve slides over a notched part on the edge of the board whereupon sit some exposed/un-insulated traces. Flat conductors encased within a plastic bit are slid into contact with them. There is no mechanism but friction to keep the 'connector' in place. Entirely inadequate. It is not designed for repeated make/break insertion/removal. If subjected even to a low number of such operations (design spec is 50), it will fail. (5 000 for an eSATA connector). If I have to repeatedly disconnect-connect a drive during testing, I replace the cable as a matter of routine." I am interested in knowing whether others have encountered this problem and how common place it is? TIA -- Gerry ~~~~ FCA Stourport, England Enquire, plan and execute ~~~~~~~~~~~~~~~~~~~ |
#19
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Sata cabling
The last time I experienced similar problems, which led to disks failing the
manufacturers test utility, it was as a result of a slightly iffy pwr supply, that when put in another PC sometime later, went bang Pwr supply & disks (2) all replaced under warranty from reputable makers (Samsung & TruePower) "Gerry" wrote in message ... I have had a disk connection problem which seems to relate to failing sata cables. The BIOS has failed intermittently to detect one or both hard drives. The problem was more obvious with the master drive so I replaced the cable 14 days ago and there was no further problem until this morning. The problem this morning was the slave drive so I have replaced the cable for that drive. It has now been working for a bit over two hour. The problem first became apparent a month ago when I found the system would freeze after it had been running some time. Resetting sometimes worked and sometimes resulted in a failed boot. Eventually the system would boot but the problem would happen again some hours later or the next day. Sometimes there have been Event Viewer reports -mainly ID: 11 referring to the Controller. Often the problem is unreported. This is probably because the Error is occurring before Event Viewer starts. From a friend I got these comments. "In my view, the SATA 'Connector' is an engineering blunder. A sort-of flat sleeve slides over a notched part on the edge of the board whereupon sit some exposed/un-insulated traces. Flat conductors encased within a plastic bit are slid into contact with them. There is no mechanism but friction to keep the 'connector' in place. Entirely inadequate. It is not designed for repeated make/break insertion/removal. If subjected even to a low number of such operations (design spec is 50), it will fail. (5 000 for an eSATA connector). If I have to repeatedly disconnect-connect a drive during testing, I replace the cable as a matter of routine." I am interested in knowing whether others have encountered this problem and how common place it is? TIA -- Gerry ~~~~ FCA Stourport, England Enquire, plan and execute ~~~~~~~~~~~~~~~~~~~ |
#20
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Sata cabling
The point is, there is no practical design possible that will allow a
parallel cable to reach the transfer rates of a serial one, for the reasons stated. Note the emphasis on the word practical (meaning realizable) - not theoretical (such as with a half meter wide cable, and/or shielded cable(s,) or whatever). (Shielded cables suffer from increased capacitance which limits their transfer rate, so even if each data signal cable (16 for 16 bit, or 32 for a 32 bit) were shielded, it's still a no go). JS wrote: Yes I know about 40 vs 80 design, what I'm talking about is a total redesign. And they do have round PATA cables, not rated any faster but they are not wide and flat. -- JS http://www.pagestart.com "Bill in Co." wrote in message ... They already tried that with the 80 conductor fast ATA cables. While it helped out a lot, it sure couldn't even come close to SATA. Now, if you want a 40 or 80 conductor parallel cable that's a meter wide, with very wide separation between all the signal carrying conductors (of which there are a LOT, for parallel)..... perhaps that might work. :-) Bottom line: it's not at all practical. JS wrote: A cable redesign could eliminate the crosstalk. -- JS http://www.pagestart.com "Bill in Co." wrote in message ... On the surface, that makes sense - but only on the surface. Let me explain: In practice, it's a false assumption due to the inherent crosstalk problems between adjacent signal carrying conductors in the Parallel ATA cable. And THAT limits the max transfer rate. OTOH, Serial cables do NOT have that problem, since only a single line is carrying the data. Hence, serial cables (like in SATA) can be, and are, much faster. JS wrote: Not crazy over the SATA connectors either. SATA or Serial ATA has another design flaw in that by nature serial data transfers can never be as fast as parallel. -- JS http://www.pagestart.com "Gerry" wrote in message ... I have had a disk connection problem which seems to relate to failing sata cables. The BIOS has failed intermittently to detect one or both hard drives. The problem was more obvious with the master drive so I replaced the cable 14 days ago and there was no further problem until this morning. The problem this morning was the slave drive so I have replaced the cable for that drive. It has now been working for a bit over two hour. The problem first became apparent a month ago when I found the system would freeze after it had been running some time. Resetting sometimes worked and sometimes resulted in a failed boot. Eventually the system would boot but the problem would happen again some hours later or the next day. Sometimes there have been Event Viewer reports -mainly ID: 11 referring to the Controller. Often the problem is unreported. This is probably because the Error is occurring before Event Viewer starts. From a friend I got these comments. "In my view, the SATA 'Connector' is an engineering blunder. A sort-of flat sleeve slides over a notched part on the edge of the board whereupon sit some exposed/un-insulated traces. Flat conductors encased within a plastic bit are slid into contact with them. There is no mechanism but friction to keep the 'connector' in place. Entirely inadequate. It is not designed for repeated make/break insertion/removal. If subjected even to a low number of such operations (design spec is 50), it will fail. (5 000 for an eSATA connector). If I have to repeatedly disconnect-connect a drive during testing, I replace the cable as a matter of routine." I am interested in knowing whether others have encountered this problem and how common place it is? TIA -- Gerry ~~~~ FCA Stourport, England Enquire, plan and execute ~~~~~~~~~~~~~~~~~~~ |
#21
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Sata cabling
Well you know the width of a SATA cable.
Serial data transfer right. Take 4 SATA cables in parallel to a Hard Drive that has four SATA connectors. What do you have ... parallel data transfer (4 wide SATA). Now the data xfer rate should be 4 times faster than a single SATA cable and the cable width would be no wider than a PATA cable. Now I know this is a design stretch, but if you have a hard drive with Integrated SATA Electronics, how hard could it be to repeat the circuit design 3 more times to get what I'll call a SATA IIx4 interface. Problem is I doubt the current level of a Hard Drive's mechanical rotation, read/write data rates and buffer size would be able to feed a 4 wide SATA connection. -- JS http://www.pagestart.com "Bill in Co." wrote in message ... The point is, there is no practical design possible that will allow a parallel cable to reach the transfer rates of a serial one, for the reasons stated. Note the emphasis on the word practical (meaning realizable) - not theoretical (such as with a half meter wide cable, and/or shielded cable(s,) or whatever). (Shielded cables suffer from increased capacitance which limits their transfer rate, so even if each data signal cable (16 for 16 bit, or 32 for a 32 bit) were shielded, it's still a no go). JS wrote: Yes I know about 40 vs 80 design, what I'm talking about is a total redesign. And they do have round PATA cables, not rated any faster but they are not wide and flat. -- JS http://www.pagestart.com "Bill in Co." wrote in message ... They already tried that with the 80 conductor fast ATA cables. While it helped out a lot, it sure couldn't even come close to SATA. Now, if you want a 40 or 80 conductor parallel cable that's a meter wide, with very wide separation between all the signal carrying conductors (of which there are a LOT, for parallel)..... perhaps that might work. :-) Bottom line: it's not at all practical. JS wrote: A cable redesign could eliminate the crosstalk. -- JS http://www.pagestart.com "Bill in Co." wrote in message ... On the surface, that makes sense - but only on the surface. Let me explain: In practice, it's a false assumption due to the inherent crosstalk problems between adjacent signal carrying conductors in the Parallel ATA cable. And THAT limits the max transfer rate. OTOH, Serial cables do NOT have that problem, since only a single line is carrying the data. Hence, serial cables (like in SATA) can be, and are, much faster. JS wrote: Not crazy over the SATA connectors either. SATA or Serial ATA has another design flaw in that by nature serial data transfers can never be as fast as parallel. -- JS http://www.pagestart.com "Gerry" wrote in message ... I have had a disk connection problem which seems to relate to failing sata cables. The BIOS has failed intermittently to detect one or both hard drives. The problem was more obvious with the master drive so I replaced the cable 14 days ago and there was no further problem until this morning. The problem this morning was the slave drive so I have replaced the cable for that drive. It has now been working for a bit over two hour. The problem first became apparent a month ago when I found the system would freeze after it had been running some time. Resetting sometimes worked and sometimes resulted in a failed boot. Eventually the system would boot but the problem would happen again some hours later or the next day. Sometimes there have been Event Viewer reports -mainly ID: 11 referring to the Controller. Often the problem is unreported. This is probably because the Error is occurring before Event Viewer starts. From a friend I got these comments. "In my view, the SATA 'Connector' is an engineering blunder. A sort-of flat sleeve slides over a notched part on the edge of the board whereupon sit some exposed/un-insulated traces. Flat conductors encased within a plastic bit are slid into contact with them. There is no mechanism but friction to keep the 'connector' in place. Entirely inadequate. It is not designed for repeated make/break insertion/removal. If subjected even to a low number of such operations (design spec is 50), it will fail. (5 000 for an eSATA connector). If I have to repeatedly disconnect-connect a drive during testing, I replace the cable as a matter of routine." I am interested in knowing whether others have encountered this problem and how common place it is? TIA -- Gerry ~~~~ FCA Stourport, England Enquire, plan and execute ~~~~~~~~~~~~~~~~~~~ |
#22
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Sata cabling
If we're talking about a true parallel interface, and a 32 bit data bus, 32
separate conductors are required JUST for that part of the interface alone. And for a 16 bit data bus, it would be 16 conductors, minimum. The problem with the required size of the connectors to accommodate all that is pretty obvious. Heck, even the normal 40 or 80 conductor PATA connectors, as small as they were, presents a physical problem. The Ultra ATA 80 conductor ones simply interleaved ground wires between all the data wires (to decrease the crosstalk problem) to raise the max transfer rates. JS wrote: Well you know the width of a SATA cable. Serial data transfer right. And it's pretty small. Especially in comparison to any PATA ones! Take 4 SATA cables in parallel to a Hard Drive that has four SATA connectors. What do you have ... parallel data transfer (4 wide SATA). But that's not true and complete parallel data transfer, which requires separate conductors for EACH data bit being transferred. (16 for 16 bit data bus, 32 for 32 bit data bus), to gain the theoretical potential advantage of parallel transfer. Now the data xfer rate should be 4 times faster than a single SATA cable and the cable width would be no wider than a PATA cable. I doubt if just doing that is really worth all the increased cost and complexity. Now I know this is a design stretch, but if you have a hard drive with Integrated SATA Electronics, how hard could it be to repeat the circuit design 3 more times to get what I'll call a SATA IIx4 interface. Problem is I doubt the current level of a Hard Drive's mechanical rotation, read/write data rates and buffer size would be able to feed a 4 wide SATA connection. And also - it would still only be 4 wide. That's nothing like the improvement gained when going from PATA to SATA, so in addition to what you wrote above, it's probably not worth it. -- JS http://www.pagestart.com "Bill in Co." wrote in message ... The point is, there is no practical design possible that will allow a parallel cable to reach the transfer rates of a serial one, for the reasons stated. Note the emphasis on the word practical (meaning realizable) - not theoretical (such as with a half meter wide cable, and/or shielded cable(s,) or whatever). (Shielded cables suffer from increased capacitance which limits their transfer rate, so even if each data signal cable (16 for 16 bit, or 32 for a 32 bit) were shielded, it's still a no go). JS wrote: Yes I know about 40 vs 80 design, what I'm talking about is a total redesign. And they do have round PATA cables, not rated any faster but they are not wide and flat. -- JS http://www.pagestart.com "Bill in Co." wrote in message ... They already tried that with the 80 conductor fast ATA cables. While it helped out a lot, it sure couldn't even come close to SATA. Now, if you want a 40 or 80 conductor parallel cable that's a meter wide, with very wide separation between all the signal carrying conductors (of which there are a LOT, for parallel)..... perhaps that might work. :-) Bottom line: it's not at all practical. JS wrote: A cable redesign could eliminate the crosstalk. -- JS http://www.pagestart.com "Bill in Co." wrote in message ... On the surface, that makes sense - but only on the surface. Let me explain: In practice, it's a false assumption due to the inherent crosstalk problems between adjacent signal carrying conductors in the Parallel ATA cable. And THAT limits the max transfer rate. OTOH, Serial cables do NOT have that problem, since only a single line is carrying the data. Hence, serial cables (like in SATA) can be, and are, much faster. JS wrote: Not crazy over the SATA connectors either. SATA or Serial ATA has another design flaw in that by nature serial data transfers can never be as fast as parallel. -- JS http://www.pagestart.com "Gerry" wrote in message ... I have had a disk connection problem which seems to relate to failing sata cables. The BIOS has failed intermittently to detect one or both hard drives. The problem was more obvious with the master drive so I replaced the cable 14 days ago and there was no further problem until this morning. The problem this morning was the slave drive so I have replaced the cable for that drive. It has now been working for a bit over two hour. The problem first became apparent a month ago when I found the system would freeze after it had been running some time. Resetting sometimes worked and sometimes resulted in a failed boot. Eventually the system would boot but the problem would happen again some hours later or the next day. Sometimes there have been Event Viewer reports -mainly ID: 11 referring to the Controller. Often the problem is unreported. This is probably because the Error is occurring before Event Viewer starts. From a friend I got these comments. "In my view, the SATA 'Connector' is an engineering blunder. A sort-of flat sleeve slides over a notched part on the edge of the board whereupon sit some exposed/un-insulated traces. Flat conductors encased within a plastic bit are slid into contact with them. There is no mechanism but friction to keep the 'connector' in place. Entirely inadequate. It is not designed for repeated make/break insertion/removal. If subjected even to a low number of such operations (design spec is 50), it will fail. (5 000 for an eSATA connector). If I have to repeatedly disconnect-connect a drive during testing, I replace the cable as a matter of routine." I am interested in knowing whether others have encountered this problem and how common place it is? TIA -- Gerry ~~~~ FCA Stourport, England Enquire, plan and execute ~~~~~~~~~~~~~~~~~~~ |
#23
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Sata cabling
Does a SATA cable look anything like a PATA cable,
no it doesn't. So who is to say a high speed Parallel interface cable has to look anything like today's PATA cables. -- JS http://www.pagestart.com "Bill in Co." wrote in message ... If we're talking about a true parallel interface, and a 32 bit data bus, 32 separate conductors are required JUST for that part of the interface alone. And for a 16 bit data bus, it would be 16 conductors, minimum. The problem with the required size of the connectors to accommodate all that is pretty obvious. Heck, even the normal 40 or 80 conductor PATA connectors, as small as they were, presents a physical problem. The Ultra ATA 80 conductor ones simply interleaved ground wires between all the data wires (to decrease the crosstalk problem) to raise the max transfer rates. JS wrote: Well you know the width of a SATA cable. Serial data transfer right. And it's pretty small. Especially in comparison to any PATA ones! Take 4 SATA cables in parallel to a Hard Drive that has four SATA connectors. What do you have ... parallel data transfer (4 wide SATA). But that's not true and complete parallel data transfer, which requires separate conductors for EACH data bit being transferred. (16 for 16 bit data bus, 32 for 32 bit data bus), to gain the theoretical potential advantage of parallel transfer. Now the data xfer rate should be 4 times faster than a single SATA cable and the cable width would be no wider than a PATA cable. I doubt if just doing that is really worth all the increased cost and complexity. Now I know this is a design stretch, but if you have a hard drive with Integrated SATA Electronics, how hard could it be to repeat the circuit design 3 more times to get what I'll call a SATA IIx4 interface. Problem is I doubt the current level of a Hard Drive's mechanical rotation, read/write data rates and buffer size would be able to feed a 4 wide SATA connection. And also - it would still only be 4 wide. That's nothing like the improvement gained when going from PATA to SATA, so in addition to what you wrote above, it's probably not worth it. -- JS http://www.pagestart.com "Bill in Co." wrote in message ... The point is, there is no practical design possible that will allow a parallel cable to reach the transfer rates of a serial one, for the reasons stated. Note the emphasis on the word practical (meaning realizable) - not theoretical (such as with a half meter wide cable, and/or shielded cable(s,) or whatever). (Shielded cables suffer from increased capacitance which limits their transfer rate, so even if each data signal cable (16 for 16 bit, or 32 for a 32 bit) were shielded, it's still a no go). JS wrote: Yes I know about 40 vs 80 design, what I'm talking about is a total redesign. And they do have round PATA cables, not rated any faster but they are not wide and flat. -- JS http://www.pagestart.com "Bill in Co." wrote in message ... They already tried that with the 80 conductor fast ATA cables. While it helped out a lot, it sure couldn't even come close to SATA. Now, if you want a 40 or 80 conductor parallel cable that's a meter wide, with very wide separation between all the signal carrying conductors (of which there are a LOT, for parallel)..... perhaps that might work. :-) Bottom line: it's not at all practical. JS wrote: A cable redesign could eliminate the crosstalk. -- JS http://www.pagestart.com "Bill in Co." wrote in message ... On the surface, that makes sense - but only on the surface. Let me explain: In practice, it's a false assumption due to the inherent crosstalk problems between adjacent signal carrying conductors in the Parallel ATA cable. And THAT limits the max transfer rate. OTOH, Serial cables do NOT have that problem, since only a single line is carrying the data. Hence, serial cables (like in SATA) can be, and are, much faster. JS wrote: Not crazy over the SATA connectors either. SATA or Serial ATA has another design flaw in that by nature serial data transfers can never be as fast as parallel. -- JS http://www.pagestart.com "Gerry" wrote in message ... I have had a disk connection problem which seems to relate to failing sata cables. The BIOS has failed intermittently to detect one or both hard drives. The problem was more obvious with the master drive so I replaced the cable 14 days ago and there was no further problem until this morning. The problem this morning was the slave drive so I have replaced the cable for that drive. It has now been working for a bit over two hour. The problem first became apparent a month ago when I found the system would freeze after it had been running some time. Resetting sometimes worked and sometimes resulted in a failed boot. Eventually the system would boot but the problem would happen again some hours later or the next day. Sometimes there have been Event Viewer reports -mainly ID: 11 referring to the Controller. Often the problem is unreported. This is probably because the Error is occurring before Event Viewer starts. From a friend I got these comments. "In my view, the SATA 'Connector' is an engineering blunder. A sort-of flat sleeve slides over a notched part on the edge of the board whereupon sit some exposed/un-insulated traces. Flat conductors encased within a plastic bit are slid into contact with them. There is no mechanism but friction to keep the 'connector' in place. Entirely inadequate. It is not designed for repeated make/break insertion/removal. If subjected even to a low number of such operations (design spec is 50), it will fail. (5 000 for an eSATA connector). If I have to repeatedly disconnect-connect a drive during testing, I replace the cable as a matter of routine." I am interested in knowing whether others have encountered this problem and how common place it is? TIA -- Gerry ~~~~ FCA Stourport, England Enquire, plan and execute ~~~~~~~~~~~~~~~~~~~ |
#24
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Sata cabling
"JS" @ wrote in message ... It's was deemed a less expensive solution at the time. I have PATA 80 wire for ATA 100 and ATA 133 drives (connected using either round PATA cables or the traditional flat ribbon) plus SATA I and SATA II drives. Don't get me wrong, I'm not against SATA but they just don't deliver on the advertized speed. Plus the connector design of SATA does not give me confidence in constantly connecting Hard Drives on my "Test" computers. The HDD speed bottleneck is the platter/head transfer, not the electrical interface. No IDE drive ever transferred data at the limits of the electrical interface...platter/head was always slower than the ATAPI standard of the day. As to serial being faster, serial has many advantages over parallel when speeds become very high. For instance, jitter and skew are major factors. As speeds and cable length increase, reliable data transfer becomes less likely. Longer high-speed parallel cables are impossible unless a differential cabling system is used, such as with later versions of SCSI, and even then the length is limited. External IDE was never practical, where eSATA is just a new physical implementation of the existing SATA standard, more or less. In our experience the SATA connectors last many times longer than any IDE connector ever could. They're far from perfect, but an order of magnitude better than 40-pin connectors. -John O |
#25
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Sata cabling
"JS" @ wrote in message ... Does a SATA cable look anything like a PATA cable, no it doesn't. So who is to say a high speed Parallel interface cable has to look anything like today's PATA cables. The horse has left the barn...to late for that now. Serial is the new parallel. :-) Best example...Ethernet. May be duplex, but serial nonetheless. -John O |
#26
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Sata cabling
JohnO wrote:
"JS" @ wrote in message ... It's was deemed a less expensive solution at the time. I have PATA 80 wire for ATA 100 and ATA 133 drives (connected using either round PATA cables or the traditional flat ribbon) plus SATA I and SATA II drives. Don't get me wrong, I'm not against SATA but they just don't deliver on the advertized speed. Plus the connector design of SATA does not give me confidence in constantly connecting Hard Drives on my "Test" computers. The HDD speed bottleneck is the platter/head transfer, not the electrical interface. No IDE drive ever transferred data at the limits of the electrical interface...platter/head was always slower than the ATAPI standard of the day. As to serial being faster, serial has many advantages over parallel when speeds become very high. For instance, jitter and skew are major factors. As speeds and cable length increase, reliable data transfer becomes less likely. Longer high-speed parallel cables are impossible unless a differential cabling system is used, such as with later versions of SCSI, and even then the length is limited. Yup. And the net size of the cables and connectors needed would be impractical. External IDE was never practical, Nope. For the reasons we've both covered, now. where eSATA is just a new physical implementation of the existing SATA, standard, more or less. And kudos for some further elucidation on it. :-) |
#27
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Sata cabling
"JS" @ wrote in message ... Not crazy over the SATA connectors either. SATA or Serial ATA has another design flaw in that by nature serial data transfers can never be as fast as parallel. Totally incorrect. You may be thinking from the good old days where RS232 would never operate anywhere near as fast a Parallel (Centronic) connection (this was a limitation of the UART devices of the period, not the inherent technology). But the reality is: that if you want the fastest communication possible, it has to be serial - parallel just doesn't cut the mustard. This is because as the data rate gets faster, the signal pulses get shorter and shorter. With a parallel connection, for various technical reasons, the signal pulses travel down the parallel conductors at different speeds (known as the propagation coefficient). With long pulses, it is relatively easy to strobe the receiver when all signals are valid. But as the pulses get shorter and shorter, there comes a point where at no point in time do all the pulses have a point where the data is valid because they arrive at different times. It is worth remembering that in a transmission line that a pulse of just .01 nanoseconds duration (a long pulse by modern standards) is approximately two millimetres long. Serial communication, on the other hand, completely solves the problem because, as there is only one transmission channel, the propagation coefficient is fixed for all pulses. The principal limitation to the transmission data rate of a serial connection these days is solely the properties of the copper transmission line itself, but this can be resolved by turning to fibre optic systems. Even these have limitations dependent on the fibre material with glass being able to carry a far greater data rate than plastic. 1.33 Gb/s is the limitation of parallel technology (even with a short cable around a foot long), but serial ATA III* is already operating at 6 Gb/s. * Not to be confused with ATA 3 (an unofficial designation) which is really ATA II, . |
#28
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Sata cabling
"JS" @ wrote in message ... Well, in a crude sense think of SATA as a two lane highway compared to PATA as an 8 lane highway. If the PATA cable design was updated to handle higher transfer rates I would think that PATA could be at least 4x faster than SATA. Not possible. 1.33 Gb/s is the practical limit for a copper parallel transmission line. And an updated PATA cable need not be a giant size ribbon cable either. Just imagine if your ram memory was serial access instead of DDR2 or DDR3. Actually, serial RAM memory already exists, but it is only used in very specialised applications due to the cost. It is, of course, much much faster than the type of memory that is encountered in a PC, but PC memory is largely hamstrung because it is based on dynamic architecture which is far slower (and cheaper) than static architecture. This is why your PC has a apir of processor caches to speed RAM access up. The L2 cache is a chunk of static RAM which is about 4 times faster than the main RAM and the L1 cache is static RAM which is vastly faster than the L2 (and very expensive - which is why it isn't very big). FLASH memory is exclusively serial access. |
#29
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Sata cabling
"JS" @ wrote in message ... It's was deemed a less expensive solution at the time. I have PATA 80 wire for ATA 100 and ATA 133 drives (connected using either round PATA cables or the traditional flat ribbon) plus SATA I and SATA II drives. Don't get me wrong, I'm not against SATA but they just don't deliver on the advertized speed. Plus the connector design of SATA does not give me confidence in constantly connecting Hard Drives on my "Test" computers. It was true that when introduced, SATA I did not deliver any speed gain over (P)ATA 133, but this was due to the choice of data encoding that they employed which gave a real world speed of around 1.2 Gb/s, which was fairly close to the ATA it replaced, if slightly slower. SATA I quickly adopted something called 'Native Command Queuing' (NCQ) as an optional feature (to preserve backward compatibility) which gave it the intended data rate of 1.5 Gb/s. This technology was nothing new as SCSI disc drives had always featured it. SATA II featured NCQ as standard and thus the advertised 3 Gb/s speed was delivered. It should be remembered that the data rates represent the maximum burst speed for the data, the actual real data rate is, as ever, hampered by the drive itself having to mechanically move the read/write head and to wait for the data block to come around. But with large on disc caches that are now common, things are getting better all the time. |
#30
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Sata cabling
"Bill in Co." wrote in message ... On the surface, that makes sense - but only on the surface. Let me explain: In practice, it's a false assumption due to the inherent crosstalk problems between adjacent signal carrying conductors in the Parallel ATA cable. And THAT limits the max transfer rate. OTOH, Serial cables do NOT have that problem, since only a single line is carrying the data. Hence, serial cables (like in SATA) can be, and are, much faster. That's only part of the problem. Crosstalk can be minimised by good cable design. That was the object of the 80 conductor (P)ATA cable which placed a grounded conductor either side of each signal carrying conductor. This reduces crosstalk, but more importantly provides the signal with a transmission path that more closely resembles an 'ideal' transmission line. But it isn't the cross talk that really limits the parallel system. It's something called 'skew'. This is where the individual signals in the individual transmission lines arive at the distant end of the cable at different times. Low voltage diferential signalling was introduced on some systems to reduce crosstalk even further but there was no solution to the problem of skew. Serial systems do not suffer from skew, hence the transmission rates are higher. |
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