VOGONS


First post, by Fractal Fischer

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Hi all, I've recently gotten into vintage PC building and restoration, and after months of finding the most helpful answers to nearly all my questions here on the Vogons forum I finally decided to join in.

So I got into this whole thing looking for a challenge, and it looks like I've found one. I've got two fairly obscure but nearly identical motherboards, and one is missing the BIOS entirely. Empty socket, no chip. The other board thankfully does have its BIOS, and it's 99% identical to the first, but not quite.

The board with no BIOS is labeled as Percomp HT83C191a 9337-ACA NT2177 (ver. 1.4). Peeling back the stickers, the chips themselves are unmarked. Images available on the eBay listing linked here.

The other board is labeled as UMC 9447-BS BA1915. eBay listing with images here.
It has a 28-pin AMI BIOS in a DIP-32 socket, and the layout and components appear identical in every way to the first board with one exception: The cache is soldered instead of socketed, the cache configuration jumpers are gone (naturally), and I have suspicions that those cache chips might be fake.

According to this Award BIOS number list and various other references, these boards are rebrands of the same model and both share the same BIOS string, 40-P301-001437-00101111-072594-DGREEN-H.

I was able to find a manual for an Amptron DX-6900 ver. 1.4 motherboard, another equivalent rebrand according to multiple sources, and the information appears to be a 100% match for the Percomp board. Here's the link.

I see this whole thing as a good excuse to buy an eprom programmer and some blank chips, hopefully learn something new, and maybe even solve the actual problem if I'm lucky. At this stage though, I know just enough to start asking questions:

1. Will a programmer like this TL866CS do what I'm needing to do?
2. Do I need a particular type of flash bios chip beyond making sure it fits the DIP-32 socket and has sufficient capacity for the ROM? Does it even matter whether it's 28-pin or 32-pin?
3. If the cache on the second board is fake, I assume the BIOS will be programmed some way or another to spoof it. Is it feasible to edit the rom and correct this to make sure it uses the full 1mb of cache I'm planning to install?

Thanks in advance for any insights on this.

Reply 1 of 1, by lowlytech

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You ever find a BIOS for your PerComp board? I found this exact HT83C191A board today while at work in a box of stuff. Will test it tonight and see if it POST's. If you still need the BIOS image just let me know.

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