I'd start by cleaning all the corrosion around the battery area and checking all traces and continuity there, components included. I wouldn't call it "little".

You didn't mention which graphics card you're using.
Could this be a mismatch between the jumpers and the videocard since XTs tend to have jumpers to select which videomode to be in use. MDA/CGA40/CGA80/EGA-VGA . maybe JP3&4 .

This is a pretty unusual 8086 motherboard. I would guess it might have an Acer chipset, though not entirely sure because the branding has been blacked out. This is the first time I've seen this chipset. Normally the XT motherboards that have VLSI use single chip chipsets, but this one has four!?
It seems that "Inves" did not design the motherboard. Not sure whose logo that is. Mitac? Mylex? It doesn't appear to be on TH99.
This board has integrated HDD and FDD controllers. Do you know if it uses XTA or ATA?

Please dump the BIOS if you can. The BIOS chip appears to say "Mintek" so perhaps that's the company who really made the board.

Hi, thank you for your help. I've removed the old battery and try to clean the most I can, but I didn't change the resistors and diodes. I think this is my next step. I can't seen all traces but all that I checked was Ok.

You're right, the chipset is from Acer, and uses XTA. I think that there was an Acer XT30 or something like this very similar.

I dump the bioses as soon as I can. Thank you for your help

Weedeewee, originally when I've bought the computer the graphic card was a VGA, but I try an EGA and a MDA. I try to fiddle around with the jumpers but I didn't get any change. Thank you

This is the original graphic card

And the bioses, there are Mintek

Hi guys, I've removed all the corruption, and repair tracks broken. I had to remove the resistors and the diodes. I can't see anything in the diodes, do you guess what kind of diodes are???

Thank you!!!!

D2 & D3 look like 1N4148
D1 ... could be a germanium diode.

be sure to put your multimeter on continuity testing and in diode mode to check those.

D1 is broken... Doesn't survive.. Do you think it can be a germanium diode??

jmellidg wrote on 2021-11-17, 19:24:

D1 is broken... Doesn't survive.. Do you think it can be a germanium diode??

it kinda looks like a 1N60 diode

Welcome to the forum!

Awesome... an all-in-one XT board from the 486 era, even with onboard IDE...
That was the extreme budget range!
In a time when many computer stores had phased out 286 already...
Definitely a very special and unusual board!

weedeewee wrote on 2021-11-17, 22:40:

it kinda looks like a 1N60 diode

Could well be possible!

But, I don't think that this battery discharge protector is relevant for the bus not working.

Is it only a photo artifact, or is there some trace cut (and maybe even short) around bus line ~25 between the two rightmost slots??

This https://hwmuseum.pp.ua/motherboard/1784 ... 19]=3x8bit looks to be a very similar motherboard aside from the color
also has a bios available.

INVESTRONICA 8086 XT-plus

Can u post a pic of the back side ?

Hi! Thank you for your answers, yes retardware, this trace is cut, I identified with the -12 track and is repaired. With respect to the Russian site, I think that if its not the same is very very close!!. I'm going to buy this morning the components and try to fix all the cut traces and try to upload a picture of the back thanks!!

By the way, how can I upload the bioses, with what extension to be allowed??

the page for the mobo is active https://www.ultimateretro.net/en/motherboards/9877

compress bios in zip format and u can upload it

Hi everybody! After repair 12 cutted traces and change resistors and diodes, my baby work for the first time!! Thank you very very much for your help. I'm going to upload the bioses if it can somebody help.

Thank you!!

Glad you got this very special mobo working 😀

Great work! It's always heartwarming to see hardware resurrected, especially if it's uncommon.

I'm really curious what's in those BIOS chips. The board is using two 256kbit EPROMs, which seems like a lot for an XT.