Fairly sure that is a non flashable bios chip so there is no flash util that will help. You need an equivalant eeprom chip and a TL866.....
As for the ram it should easily support up to 16MB (or possibly 64Mb with the right SIMMS) iirc,

added: I cannot see the ram table in BIOS v2.5 but the top v2.7 from Retro does show up to 64Mb ram.

Horun wrote on 2023-10-07, 15:47:

Fairly sure that is a non flashable bios chip so there is no flash util that will help. You need an equivalant eeprom chip and a TL866.....
As for the ram it should easily support up to 16MB (or possibly 64Mb with the right SIMMS) iirc,

added: I cannot see the ram table in BIOS v2.5 but the top v2.7 from Retro does show up to 64Mb ram.

Thanks man!
To bad, i thought i could do it myself. As of the ram problem, i was wrong, it shows 3MB (3712 Kb), not 4MB. I have 4 sticks of 4MB simm ram, and it is same if i put them or 4x1MB sticks. It shows 3072Kb?

What happens if you put both the 4x4 and 4x1 simm modules ?

weedeewee wrote on 2023-10-07, 16:23:

What happens if you put both the 4x4 and 4x1 simm modules ?

7808Kb 😀

are the 4M simm modules 2 or 3 chips then you might need 8/9 chip simm modules to get the desired 16M with only 4 modules

weedeewee wrote on 2023-10-07, 16:28:

are the 4M simm modules 2 or 3 chips then you might need 8/9 chip simm modules to get the desired 16M with only 4 modules

No, they are 9chips. Could it be the BIOS v2.5 problem?

agree ! those particular 4Mb simms may have a chip density the board cannot address proper so they appear as 1Mb simms. The 3712k is because 384k is held for UMB & shadowing (making 4096), the "usable" ram is what is displayed, not the actual total.
This was fixed in later 486 BIOS versions starting about 1993 or 94 iirc and yes it MIGHT be fixed in the v2.7 bios...

Horun wrote on 2023-10-07, 16:37:

agree ! those particular 4Mb simms may have a chip density the board cannot address proper so they appear as 1Mb simms. The 3712k is because 384k is held for UMB & shadowing (making 4096), the "usable" ram is what is displayed, not the actual total.
This was fixed in later 486 BIOS versions starting about 1993 or 94 iirc and yes it MIGHT be fixed in the v2.7 bios...

So i need eeprom burner and 23c512 chip!!! Thanks a lot, i will try to change BIOS and see if that fixing the problem.
Thanks

What revision is your motherboard ? nevermind I see it in the title 🤣

fyi, https://theretroweb.com/motherboards/s/pcchip … .-2.x#downloads also lists a v2.11 bios

weedeewee wrote on 2023-10-07, 16:58:

fyi, https://theretroweb.com/motherboards/s/pcchip … .-2.x#downloads also lists a v2.11 bios

Yes, maybe this BIOS version would be better, cause now is M320-F, and this 2.11 also have CHIP-F mark???

Actually it is same 2.7 with a small insert of the TRANS-AMERITECH ENTERPRISES, Inc. as per the hex compare. Both dated internally 6/6/1992.....

Horun wrote on 2023-10-07, 17:34:

Actually it is same 2.7 with a small insert of the TRANS-AMERITECH ENTERPRISES, Inc. as per the hex compare. Both dated internally 6/6/1992.....

Thanks, so it is same thing, whatever i flash on to new eeprom!?

I wanted to buy this "flasher", but i didn't find any entry for 23C512 :
https://www.ebay.com/itm/325256013386?_trkpar … %3Avlp_homepage
Does anybody knows, some cheap Flasher that works for all those old eproms like the one here (286, 386, 486,...), and maybe for Amiga Kickstart roms?
Thanks

23c512? That isn't a programmable device.
you'll need something like a 27c512

weedeewee wrote on 2023-10-09, 18:21:

23c512? That isn't a programmable device.
you'll need something like a 27c512

On this BIOS chip (M321) it is written 23C512? So i can program 27C512, and it will work?

ffs.
https://www.easytechjunkie.com/what-is-mask-rom.htm

You can not re program the 23C512.
You will have to use something like a 27c512 or equivalent.

edit: that was the first link on google, and in hindisight, it's not the greatest. 😒

weedeewee wrote on 2023-10-09, 19:44:

ffs. https://www.easytechjunkie.com/what-is-mask-rom.htm […]
Show full quote

ffs.
https://www.easytechjunkie.com/what-is-mask-rom.htm

You can not re program the 23C512.
You will have to use something like a 27c512 or equivalent.

edit: that was the first link on google, and in hindisight, it's not the greatest. 😒

If the chip i need is 27C512, than the programmer i saw on ebay is also ok. It has entry for 27C512 😀

yes