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A thrift store computer

if memory serves, can someone verify, but pc-chips used a proprietary coast module, using the pentium style, will fry the board

Correct. The manual says "128K/256K/512K/1024KB asynchronous SRAM module supported; Future will support pipeline burst SRAM module." But I've never seen one with anything larger than the 256K module, and of course the "future" pipeline burst module never came. I don't think it's even possible to use a pipeline burst L2 cache with a 486-based system(?).
 
So I picked decent cases then (Enlight and Inwin).

The PC-Chips M919 486 motherboard needs Async SRAM (not the more common Pipeline Burst Coast module found in Pentium 1's), from what I recall last I searched it had some specific writing on the side of the module. You will need to find the correct one and change the jumpers to enable it.
 
Oh wow, I never expected this thread to be so popular.

But yeah, I know about the special ASync module from reading Red Hill's Computer Guide.

What's also interesting is that all I read of this board is nothing but "Throw it out" or "Unstable" or something like that.
I was playing some Quake yesterday on the machine and it never skipped a beat. Windows 95 hasn't thrown any white-box system errors, BSODs or GPF errors yet. It's been running very stable.
 
The M919 is one of the more stable PC Chips boards, probably because 486 technology was very mature by the time it was produced. It was pretty much the last new 486 board you could easily find at computer shows in the mid-'90s.
 
Interesting read about PC-Chips. Amazed they lasted, cause alot of what they were doing sure sounds like fraud.

Luckily, when I was young and dumb about these things in the 80s and 90s, the computer shops I dealt with only carried good quality stuff like asus and soyo.
 
There were quite a few companies selling the same exact boards as PC-Chips around that time.

I kind of liked M-tech for Pentium 1 boards, don't think they are still in business.
 
So I picked decent cases then (Enlight and Inwin).

The PC-Chips M919 486 motherboard needs Async SRAM (not the more common Pipeline Burst Coast module found in Pentium 1's), from what I recall last I searched it had some specific writing on the side of the module. You will need to find the correct one and change the jumpers to enable it.
If I recall correctly, around that time there was acute shortage of high speed SRAM so a lot of boards were shipped with just the DIP packaging; no silicon inside...
 
I recollect that initially some 80486 boards ran at 50Mhz bus speed. At any rate I could only afford a cheap integrated no-name 80486 mainboard + CPU + 4MB RAM in 1993 or 1994. By luck I managed to get 8 MB in really cheap SIMMs in 1994 or 1995 because someone had mistakenly dropped a lot of 1MB SIMMs in a computer case and I was able to buy plently for a very low price.​
 
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If I recall correctly, around that time there was acute shortage of high speed SRAM so a lot of boards were shipped with just the DIP packaging; no silicon inside...

Exactly. SRAM was expensive, so to offset this, low-end 486 boards often shipped with empty SRAM sockets, to let you add your own L2 cache later as you could afford it. But seeing all the empty DIP sockets looked cheap and ugly, and people knew that a board with no L2 cache would have poor performance. So thus "fake cache" was born: fake, empty SRAM chips to give the appearance of a preinstalled L2 cache, soldered directly to the board and paired with a patched BIOS, so the fraud could not be easily discovered.
 
DRAM and SRAM prices have been known to go up and down like crazy. I recall at one point SRAM was cheaper then DRAM and some computer maker did a 386 with no wait states using faster SRAM (or maybe it was a 286 forget). One reason from RAM prices going up was a fire at a factory in Japan I think.
 
that is why i pull the memory from all the computers i have go rid of in the past. then i always have a bit of everything if i need it. the only problem i have is i have tons of memory and it takes a long time to test it all
 
DRAM and SRAM prices have been known to go up and down like crazy. I recall at one point SRAM was cheaper then DRAM and some computer maker did a 386 with no wait states using faster SRAM (or maybe it was a 286 forget). One reason from RAM prices going up was a fire at a factory in Japan I think.

Japan or Taiwan but I also recollect prices doubling overnight at some point.​
 
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Don't knock that PC Chips M919, its a stable board if you get the right one. I had purchased one back in 1996 as a bundle deal. Oddly enough it had the AMD 5x86 133Mhz chip and 16MB of RAM. I believe the board was the latest revision as it had the non-quite COAST cache on it. I ran it from 1997-2002 as a firewall running Linux and it never skipped a beat. The board was wonky though. It refused to work with my Cirrus Logic CL-GD5428 VL-Bus video card and tech support said those cards weren't compatible. I was forced to pick up some no name brand CompUSSR special with an ArkLogic video chip (yeah, ghetto but it oddly worked great with XFree86). Another odd thing was Windows 95 never showed a Plug & Play BIOS in the device manager, even though the board should have been PnP.
 
Those PC Chips mobos are rather interesting... fake cache? Hilarious! At least the designers had some humour.
 
If you did a fresh install of 95 it would likely run a hell of a lot better. I'd stick to high-end DOS and Win3x stuff on there, myself. I know that sounds odd coming from me, but I only obsessively max out machines with hard limits - otherwise "replace the motherboard" is always an option. :p

Where did this thread come from, btw... it wasn't here before, and it's not brand new, so it must have been moved... but to the wrong section?
 
Those PC Chips mobos are rather interesting... fake cache? Hilarious! At least the designers had some humour.

The original 486 had something like 8K cache built into the CPU, the late 486 chips has 16K so not having 128-256K cache on the motherboard is not exactly going to completely kill performance. Besides on VLB systems the CPU is fighting the VLB cards over access to the memory bus wich the cache resides on anyway.
 
The original 486 had something like 8K cache built into the CPU, the late 486 chips has 16K so not having 128-256K cache on the motherboard is not exactly going to completely kill performance. Besides on VLB systems the CPU is fighting the VLB cards over access to the memory bus wich the cache resides on anyway.

I think we all know what needs to be done...
Now, finding my M919 board might be a bit difficult.
 
Unknown_K: I might know a ton about the 486 (at least I'd like to think so), but you know WAY more than me when it comes to practical application.. Thus I pose a question: I may be able to create (or participate in the creation of) a riser card for the Presario 400 series that would add up to 1MB of L2 cache to it (the chipset supports it, there just aren't any sockets for it). The box that I'd use this on runs the P24T at 84Mhz (or can run the Am5x86 at 133Mhz in an upgrade chip format), has 20MB RAM (which I may also be able to increase through modding) and a GD5420 GPU. Do you think it would make much of a difference to add the L2 to this system? The P24T has 32K of L1 cache, for reference (if you didn't know).
 
This thread still popular? o.o

If you did a fresh install of 95 it would likely run a hell of a lot better. I'd stick to high-end DOS and Win3x stuff on there, myself.
That's what I ended up doing. I wanted to run Windows 3.1 on this system but I could only find video card drivers for Windows 3.1, so it got Windows 95.
 
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