Hmmm, I've had no luck getting the 1.41 BIOS out of an EXE and into the ROM for my card today. Many highly musical 'NO VGA' post beeps was the result, 🤣. Still, got 1.30 working yay!!

Yay great success! It was exactly as you all theorised, ODD and EVEN lay on top of each other. I used the split command and then combined them back, wrote it to an EPROM and it worked first time. I've attached the new (1.30) BIOS that I made in case anyone stumbles across this thread in the future. …

Well I'll let you all know exactly what j discover tomorrow when I give the new BIOS a whizz!!

So was this by design or do you think the manufacturer made an arse of the PCB that they 'fixed' with this bodge? Maybe it was to combine from an older design with two ROMS?

Ah ha! Awesome, thanks so much for that! I'll give it a whizz tomorrow 👍

In which case for a purely hardware solution I could correct the bad address lines on the card, then allowing me to run the standard ROM? Some scalpel action and a couple of bodge wires... 🤔

Thanks so much for your reply! Ah!! So perhaps this board was originally designed to have two EPROMS (odd and even) and later it was squished down to one? How would I go about formatting my BIN to comply with that standard?

Hi everyone! I'm having something of a problem I've never seen before and I wonder if it rings a bell to anyone? I have an old ISA card based on the Cirrus Logic CL-GD5422 chipset. Card is in good condition and works fine, but it has a home programmed EPROM on it with the original 1.00b BIOS that …

Ah thank you so much for checking! It looks like someone borrowed u18, u17, u13 and u21 from this board. Also there might be a resistor or cap missing off of u13 there. Be nice if they'd brought them back!! 😁

Hi! I'm currently working through a backlog of damaged / unknown / dumped older motherboards and I've came across one that I think might be worth some time to fix up. Only one small issue: it's missing some chips and I can't find a decent high res picture of the board anywhere to figure out which …

"P9436ZL", they are the three or four 74f256 chips that have been (very carefully, thankfully!) removed from the board, along with some inductors and one or two surface mount resistors. I've put new ones back on :) I notice there's no cache - and no jumper option for no cache, so I think I'm going …

Hi everyone! Long time lurker, first time poster! I'm currently trying to revive a um4981 motherboard that I found in the back of a cupboard in my hardware lab. It's missing a few components, and I'm wondering if anyone could help? I know there's not going to be a schematic of BOM anywhere probably, …