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#16
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O.T. Cleaning computer
On Fri, 30 Nov 2018 20:12:58 -0800 (PST), Mark Twain
wrote: I meant (rivets) not(2) of course.. Maybe I can get a set of anti-static brushes that can get in-between the fan blades to clean/loosen the dust and then vacuum? I don't think they thought much about maintenance when they build computers. . Robert They do think a lot about ESD tho and if you don't remove any grounds or detach any components you are pretty safe with a vacuum as long as you don't actually touch the components with the nozzle. Safest is a static safe "toner" vac like the 3M. The hose is bonded and the crevice tool is carbon fiber. |
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#17
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O.T. Cleaning computer
On Fri, 30 Nov 2018 20:18:41 -0800 (PST), Mark Twain
wrote: In passing... had (4) power outages today all while I was online! Thankfully the 8500 came back up OK each time. Robert We have been pulling the plug on our computers for 30 years. They whine about it but if you are not updating an important data file, nothing bad will happen. |
#18
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O.T. Cleaning computer
As I'm on a very limited budget I'm not going to be
able to invest in such equipment and I have other items I need to buy first. Robert |
#19
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O.T. Cleaning computer
I was concerned about the HD crashing.
Robert |
#20
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O.T. Cleaning computer
Mark Twain wrote:
I was concerned about the HD crashing. Robert The hard drive has "emergency retract". It's supposed to use the spindle motor as a generator, to provide enough power to move the arm back to the resting position. Whether that's how it works, who can be sure. The one and only web site (HGST) which "explained" hard drive technology, is closed now. The heads aren't really intended to "land" on the platter, because of the possibility of stiction. At one time, like my 250MB Quantum drive, there was no ramp, and no place for the heads to go. And the spindle would spin down, and the heads would rest on a "textured" landing surface. And the heads used to "stick", requiring the user to tap the drive to try to free them up again. That's why they put in a landing ramp. On the old wash-tub (computer mainframe) drives, they used violence at shutdown. There is a large capacity for energy storage, and the capacitor is dumped into the voice coil. The radial arm retracts at high speed and hits a "stop" with a resounding thud. It's a wonder the heads don't fall off. Modern drives, when putting the arm up the ramp, are gentle by comparison. ******* I found a picture of a fan assembly similar to yours, that shows screws for both levels. There are some round-head screws holding the fan to the heatsink. https://www.amazon.com/DW014-Heat-As...dp/B00ZSXMC7I/ If you're had one of the fan screws loose, you could always examine it to see how it works. For better or worse, the technique seems to be "metal screw wedges in between aluminum surfaces", which could kick up debris. It would be unnatural for them to use a tap and thread the heatsink and use a machine screw instead. For Dell, at least part of the design of their PC cases, is for speed of assembly. But it could be that the heatsink assembly is made in some other factory, in which case driving screws in an interference fit into the aluminum might be the way they do it. For the companies that make these, what they want to do is make a long bar of heatsinks with aluminum extrusion, then saw off chunks of heatsink (like cutting a baloney). They don't really want to do any more machining than that. Cutting threads into the aluminum, would go against their "philosophy". Where it gets more interesting, is with copper core aluminum heatsinks. Where a copper slug is inserted into the aluminum. And that requires elevated temperature or something. So that's a level above "baloney slicing" on the factory floor. The copper slug method is one level above plain aluminum heatsinks, and reduces the thermal distance to the fins. These are three ways to build CPU heatsinks. These are in increasing order of cooling capacity. 1) plain aluminum 2) aluminum with copper slug in center (contacts CPU) 3) heatpipe cooler to distribute heat to the fins And for the larger video cards, some of those use 4) vapor chamber (similar to heatpipe), a box with a couple drops of alcohol or similar, near the base. Heatpipes move heat better than a solid copper piece of the same diameter. They work until you exceed the "capacity" and the fluid inside can't condense because the heat flux is too great for them. This would cause the temperature to shoot up, because the transport mechanism no longer works. Video cards can use up to around 250W. Intel will be coming out with a CPU soon, that uses more than that. (It'll have at least two CPU dies inside, from a regular processor.) It's a Xeon for servers or something. It will be interesting to see how they cool it. Water cooling used by hobbyists, wouldn't really be an option for a server room. The cooler design must be reliable. Paul |
#21
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O.T. Cleaning computer
Mark Twain wrote:
As I'm on a very limited budget I'm not going to be able to invest in such equipment and I have other items I need to buy first. Robert Where the fan blows down onto the heatsink, the dust will be near the top of the heatsink. A tissue moistened with a bit of isopropyl might work, and a pair of precision tweezers for picking out stuff that doesn't belong. That's better than nothing. You can clean it manually, with hand tools, being careful to not stress the fan hub too much. I learned my lesson, by ruining the Coolermaster fan on my current heatsink, and having to replace it. The screws on mine were relatively easy to remove, and a standard fan could take its place. That's a requirement for me when I buy coolers, is making sure a regular fan functions as a replacement. Paul |
#22
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O.T. Cleaning computer
Mark Twain wrote:
In passing... had (4) power outages today all while I was online! Thankfully the 8500 came back up OK each time. Robert I use a UPS here (SPS type). It covers the one second outages well. The other kinds of power outages, range from 20 minutes to 2 hours, and the UPS doesn't stay up long enough for those. The price of sinewave output has come down. At one time, something like this was $1000. https://www.newegg.com/Product/Produ...82E16842301699 Half Load: 11.4 Minutes Full Load: 3.3 Minutes 1350 VA / 810 Watts Topology - Line Interactive Transfer Time - 8ms typical : 10 ms maximum So that's similar in some ways, to an SPS, only with Sinewave output instead of modified square wave. (An SPS runs ice-cold normally, as it isn't doing anything active when not called upon. Double-conversion UPSes on the other hand, have fan cooling, because they're always working, no matter what.) When that unit is boosting the output, it would need to be running in some capacity (it can compensate for a brown-out on the power company side). With a single idling PC and small LCD monitor connected to one of those, you'd probably get 45 minutes from it. Still not enough for a 2 hour outage, where the power truck has to come out. There was a time, where we got two one-second outages per day here. And I decide to get a UPS to cover over those outages so the PC wouldn't crash. I got about ten years out of the battery, before it needed to be replaced (the UPS tests the battery about once a day, to see if the battery impedance is correct - it doesn't measure the hold up time or anything, as a test). Paul |
#23
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O.T. Cleaning computer
In message , Paul
writes: [] Where the fan blows down onto the heatsink, the dust will be near the top of the heatsink. A [] What proportion of such fans blow onto the heatsink, as opposed to sucking off the heatsink - about 50-50, or is one type much commoner than the other? I know "clean box" cabinets tend to operate under positive pressure, which is counter-intuitive (though does make sense when you think it through), but there the concentration is on air filtration, rather than cooling. JPG Have you ever disagreed with a petition, but been frustrated that there's no way you can *show* that you disagree? If so, visit 255soft.uk - and please pass it on, especially to twitter, facebook, gransnet/mumsnet, or any such. -- J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf I long for the commercialised Christmas of the 1970s. It's got so religious now, it's lost its true meaning. - Mike [{at}ostic.demon.co.uk], 2003-12-24 |
#24
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O.T. Cleaning computer
In message , Paul
writes: Mark Twain wrote: In passing... had (4) power outages today all while I was online! Thankfully the 8500 came back up OK each time. Robert I use a UPS here (SPS type). It covers the one second outages well. The other kinds of power outages, range from 20 minutes to 2 hours, and the UPS doesn't stay up long enough for those. [] I use a "poor man's UPS" - I use laptops almost exclusively. There has recently been a long thread on comp.mobile.android (which may have spread to other 'groups) about what policy gives the best battery longevity, but even for those that just leave the power connected all the time as I do (I'm pretty sure that's _not_ best for battery longevity, though _how_ much difference it makes is far from clear), the battery will usually give enough to get over up to 20-30 minutes (and make one-second outages totally not a problem. Even a battery on its last legs will usually hold out enough to allow a controlled shut down. (I haven't got round to making up a battery box for my modem/router, though.) JPG Have you ever disagreed with a petition, but been frustrated that there's no way you can *show* that you disagree? If so, visit 255soft.uk - and please pass it on, especially to twitter, facebook, gransnet/mumsnet, or any such. -- J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf Democracy is when two wolves and a sheep decide what is for dinner. (quoted by) Ipraylam, 2015-07-13 |
#25
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O.T. Cleaning computer
J. P. Gilliver (John) wrote:
In message , Paul writes: [] Where the fan blows down onto the heatsink, the dust will be near the top of the heatsink. A [] What proportion of such fans blow onto the heatsink, as opposed to sucking off the heatsink - about 50-50, or is one type much commoner than the other? I know "clean box" cabinets tend to operate under positive pressure, which is counter-intuitive (though does make sense when you think it through), but there the concentration is on air filtration, rather than cooling. JPG Most of these will blow the air downwards, which can help cool the Vcore regulator or any other VRM-like portions near the CPU. Drawing air upwards has been tried, but doesn't work quite as well. The design the OP has, has no plenum to speak of, and a "suction" design would need a plenum to maintain pressure. ******* Dust in computer cases, is a function of positive or negative pressure. And fan location makes a difference, in terms of "stirring" the dust until the air vents out the back. With some fan installations "dumping" more of the dust load into the PC, than others. Some PCs have dust filters on the front. All that this does, is guarantee a cleaning job every three months. And you have to position the PC, so you can pull the washable filter out of the computer case (at the bottom front). Without the dust filter, the same PC can run for a year or two, without a cleaning. Paul |
#26
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O.T. Cleaning computer
J. P. Gilliver (John) wrote:
In message , Mr Pounder Esquire writes: [] Oh, I've always earthed myself to a radiator before I take the desktop into the garage. Good idea, but voltage is relative - it's more important that you touch (an exposed metal part of) the chassis before touching anything inside - in theory, it probably doesn't matter if you're at 1 kV, if the chassis is also at 1 kV. (Well, I exaggerate for effect, but YKWIM.) If the chassis and you are both grounded, even better. Often achievable by leaving the mains lead (US: line cord) plugged in, assuming it's a 3-pin plug. I need to take it into the garage and take the panels off before I can touch the chassis. Then I have to find an earth. |
#27
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O.T. Cleaning computer
Yes that's it and as you can see I have to use
a screwdriver small enough to fit through the hole to get at the screws. 250W for a video card! no wonder the video card we installed on the 780 had a fan on it. Robert |
#28
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O.T. Cleaning computer
Ok and thanks for the advice,.. as I say
I don't want to mess up anything for the sake of cleaning. Robert |
#29
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O.T. Cleaning computer
I don't have anything fancy like that but have a APC
surge arrest https://www.apc.com/shop/us/en/produ...r=SEC-756-GOO-[53166061159]-[269259981065]-S-[] Robert |
#30
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O.T. Cleaning computer
In message , Mr Pounder Esquire
writes: J. P. Gilliver (John) wrote: In message , Mr Pounder Esquire writes: [] Oh, I've always earthed myself to a radiator before I take the desktop into the garage. Good idea, but voltage is relative - it's more important that you touch (an exposed metal part of) the chassis before touching anything inside - in theory, it probably doesn't matter if you're at 1 kV, if the chassis is also at 1 kV. (Well, I exaggerate for effect, but YKWIM.) If the chassis and you are both grounded, even better. Often achievable by leaving the mains lead (US: line cord) plugged in, assuming it's a 3-pin plug. I need to take it into the garage and take the panels off before I can touch the chassis. Then I have to find an earth. That might be one case where, indeed, you and the chassis are at the same potential (thus you're unlikely to cause damage by a discharge), even if that potential isn't earth potential. (Although I'm surprised you don't have a handy earth in your garage - don't you have power there, e. g. for a battery-charger? If so, I'd _hope_ it has earth terminals!) JPG Ever been frustrated that you can't *disagree* with a petition? If so, visit 255soft.uk - and please pass it on, too. -- J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf Old soldiers never die - only young ones |
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