Afaik there is no motherboard that can program UV EPROM on board, so you'll need an external programmer. But I think the problem is not with the EPROM, but most likely jumpers issue.

kalohimal wrote on 2020-07-08, 12:19:

Afaik there is no motherboard that can program UV EPROM on board, so you'll need an external programmer. But I think the problem is not with the EPROM, but most likely jumpers issue.

I was thinking it too but I've seen an ebay auction of the same mainboard sold with a Dx2-66 and I checked in that photo each single jumper and they were exactly as I found it... in fact I too was thinking that usually bios doesn loose the data that easily but it happened on some mobo that the eeprom was gone recently on a socket 7 one that had one that could not be flashed in some internal area. But at least it had the ISA boot recovery option still alive..
Maybe it's cheaper to buy an ISA debug card than a flashing kit..

Yes I think a POST diagnostic card is much more useful. Usually the ISA card also has PCI so it can be used on more modern PCs too.

And for UV EPROM, not only you'll need a programmer but you'll also need an eraser, unless you have extra blank UV EPROMs.

I've seen that these UV eprom are sold on ebay already erased but the flasher may be expensive.. I remember reading also that something could be checked with the multimeter to see if the cpu/bios is starting or something.
I've the PCI post card unfortunately when I bought it I didn't think to the ISA possibility..

Mine is this version, nice thing is it has a speaker on board so you could just connect the speaker output to it. I have another "smart" post card with an LCD display which would interpret the code for you but unfortunately it's PCI only.

I just bought a flasher and a few blank EPROM chips expecting to need to put an LBA BIOS on a 486 motherboard I just bought, only for it to arrive and already have that updated BIOS on it.
OP, is there a particular 64kilobyte image you're looking for? Maybe you can give me a use for it.

jakethompson1 wrote on 2020-07-08, 21:28:

I just bought a flasher and a few blank EPROM chips expecting to need to put an LBA BIOS on a 486 motherboard I just bought, only for it to arrive and already have that updated BIOS on it.
OP, is there a particular 64kilobyte image you're looking for? Maybe you can give me a use for it.

Unfortunately I didn't find a bios for the mainboard of the first post linked thread so I've not yet found a compatible one. While I've found a similar not equivalent Acer bios board having the same eprom type and similar config

==== 4alm002.zip ========================================
Name: ???
Revision: REV 1.0
CPU/FPU: 486 (in LIF socket)
Chipset: ALi M1429, M1431
ICs: IS61C256AH-20N (9), SC425APB, JETkey V5.0
Memory: SIMM-30 (8)
Exp. slots: ISA-8 (1), ISA-16 (3), VLB (3)
Id string: ???
BIOS: AMI
ROM: M27C512-15XFI (64k)
File: 4alm002.bin

but sure is not its own cause from the bios name I found it should be an Acer board beside having similar config. I wish I'd find the exact bios to exclude is a bios problem and not something else that can't make any video signal out of it.

If you need to burn a bios rom, you could build yourself a tommyprom and can swap the uveprom for a pin compatible eeprom.
they are cheap to make

https://github.com/TomNisbet/TommyPROM