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#76
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No sense in reviving old computers
philo wrote:
On 02/20/2017 11:15 PM, Mike S wrote: On 2/20/2017 2:03 AM, Ant wrote: Since we're talking about old school computers. Here are mine: http://zimage.com/~ant/antfarm/about/toys.html ... do you ever max out your 6GB RAM? Speaking of maxing out RAM about 12 years ago someone who was getting rid of junk gave me an ISA, RAM extension board. I put it in my Zenith Data Systems 286 and got 16 megs of RAM recognized. The max amount a 286 can address! At the time the machine was made 16 megs of RAM would have been (almost) an impossibility and probably cost over $50,000 The RAM was probably bigger than the biggest disk drive at the time :-) Paul |
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#77
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No sense in reviving old computers
On Tue, 21 Feb 2017 13:52:09 -0500, Paul
wrote: philo wrote: [snip] At the time the machine was made 16 megs of RAM would have been (almost) an impossibility and probably cost over $50,000 The RAM was probably bigger than the biggest disk drive at the time :-) Hardly. I bought a system (XT-compatible) with a 20 MB hard drive in 1988. That was a run-of-mill size then. Sincerely, Gene Wirchenko |
#78
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No sense in reviving old computers
On 02/21/2017 12:52 PM, Paul wrote:
philo wrote: On 02/20/2017 11:15 PM, Mike S wrote: On 2/20/2017 2:03 AM, Ant wrote: Since we're talking about old school computers. Here are mine: http://zimage.com/~ant/antfarm/about/toys.html ... do you ever max out your 6GB RAM? Speaking of maxing out RAM about 12 years ago someone who was getting rid of junk gave me an ISA, RAM extension board. I put it in my Zenith Data Systems 286 and got 16 megs of RAM recognized. The max amount a 286 can address! At the time the machine was made 16 megs of RAM would have been (almost) an impossibility and probably cost over $50,000 The RAM was probably bigger than the biggest disk drive at the time :-) Paul The machine came with 512k of on-board RAM. it was all discrete memory chips . I'd have to look at it...but they were probably 10k or 20 k each |
#79
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No sense in reviving old computers
philo wrote:
On 02/21/2017 12:52 PM, Paul wrote: philo wrote: On 02/20/2017 11:15 PM, Mike S wrote: On 2/20/2017 2:03 AM, Ant wrote: Since we're talking about old school computers. Here are mine: http://zimage.com/~ant/antfarm/about/toys.html ... do you ever max out your 6GB RAM? Speaking of maxing out RAM about 12 years ago someone who was getting rid of junk gave me an ISA, RAM extension board. I put it in my Zenith Data Systems 286 and got 16 megs of RAM recognized. The max amount a 286 can address! At the time the machine was made 16 megs of RAM would have been (almost) an impossibility and probably cost over $50,000 The RAM was probably bigger than the biggest disk drive at the time :-) Paul The machine came with 512k of on-board RAM. it was all discrete memory chips . I'd have to look at it...but they were probably 10k or 20 k each The chips were all power-of-two, with values like 16Kx1, 16Kx4, 64Kx4, and so on. The older DRAM chips ran on three rails, whereas static RAM only needed +5V. The DRAM chips also had an undershoot problem, which meant if the waveforms wiggle just a little bit, coming from the memory controller, it causes current to flow into the substrate of the memory chip. The engineers hated this, because basically every design they did was "tempting fate". A significant change, is on one generation of memory, they removed the hard clamp to ground, and the spec for the memory allowed something like a 2V undershoot. This took a lot of pressure off the poor guys still doing DRAM design. They could "almost relax". If we fast forward to modern times, the designs don't have nearly as much "drama" involved. I eventually did a design with DRAM, and it... just worked. And I had practically nothing to do with the success :-) On my design, the memory chips were soldered down and not on a DIMM (like you might find on a tablet or smart phone). If a board were to be tested and have "bad RAM", it meant using the hot air station to replace it. All the first batch of boards worked, and again, that's a testament to the incoming quality of the memory we were buying. We didn't get floor sweepings. Paul |
#80
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No sense in reviving old computers
On 02/21/2017 09:48 PM, philo wrote:
[snip] The machine came with 512k of on-board RAM. it was all discrete memory chips . I'd have to look at it...but they were probably 10k or 20 k each The computer I had that had 512KB on-board had 2 banks of 256Kb * 1 chips (18 RAM chips total, since 1 chip per bank was for parity). Note the difference between bytes (B) and bits (b). -- Mark Lloyd http://notstupid.us/ "The state (the U.S. Constitution) has not the right to leave every man free to profess and embrace whatever religion he may desire." [Pope Pius IX] |
#81
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No sense in reviving old computers
On 02/21/2017 05:05 PM, Gene Wirchenko wrote:
[snip] Hardly. I bought a system (XT-compatible) with a 20 MB hard drive in 1988. That was a run-of-mill size then. Yes. I got a 30MB, which was the same physical drive with a RLL controller. It still allowed the user to do a low-level format (LLF). IIRC, I would have to use DEBUG and give a command like GC000:00CC to run a LLF program on the controller ROM. Also, Spinrite could do a LLF. Sincerely, Gene Wirchenko -- Mark Lloyd http://notstupid.us/ "The state (the U.S. Constitution) has not the right to leave every man free to profess and embrace whatever religion he may desire." [Pope Pius IX] |
#82
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No sense in reviving old computers
On Sat, 18 Feb 2017 20:40:12 -0600, philo wrote:
On 02/18/2017 04:49 AM, Ant wrote: sctvguy1 wrote: On Thu, 16 Feb 2017 14:30:20 -0600, philo wrote: On 02/15/2017 03:12 PM, Wildman wrote: On Wed, 15 Feb 2017 21:53:38 +0100, Linea Recta wrote: "philo" schreef in bericht news I was given a 2ghz AMD machine with 2 gigs of RAM and a bad HD with XP. In theory that should have been ok for Win7 I replaced the drive and installed Win7 The machine must have been 15 years old and though Win7 would install, the CPU has no SSE2 so I was not able to install any new browser due to lack of H/W support. The machine has now been sent to the recycler So it had an older processor than Pentium 4? Intel started SSE2 with the P4 in 2001 but AMD did not support it until the release of the Opteron and Athlon 64 chips in 2003. Thanks for the info. It did not break my heart to recycle a 16 year old comptuer As long as it was not an IBM PS/2! Why? I had my own PS/2 model 30 286 10 Mhz and a borrowed P70 386 portable back then. I hated Microchannel Architecture (MCA) in the 386. 286 was OK without its MCA, but dang slow. My PS/2 runs win95 extremely well! I am looking for a PS/2 to run OS/2. I am having a hard time finding on in my area. |
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