VOGONS

Coreboot port for UM8881/6

Topic actions

First post, by pc2005

Posted on 
User metadata
Rank Newbie
Rank
Newbie

Started in "UMC8881/8886 Datasheet" thread (seems I have no links allowed here) . As the development is experimental, let's use this thread as a discussion for people who wants to try it.

Summary:

  • support for Biostar MB-8433UUD motherboard with Am5x86-133 (probably other enhanced 486 too, most of the things is hardwired though)
  • better SIMM support than original Award BIOS (I think two different modules in slot 3 and 4 failed to boot, my enumeration should use bigger or limits the bigger to the size of the smaller)
  • SeaBIOS able to boot from 3TB drive, SSD, CDROM, DVD
  • support for PCI-PCIe adapter (with a 3.3V supply mod)
  • support for PCIe SATA cards, board can boot from PCIe SATA controller
  • ability to enumerate and boot on AMD RX460 PCIe GPU (possibly any modern GPUs which still have standard optionROM)
  • opengl acceleration in linux (half life viewer, clasicube, furmark and blender!) .. also it can enumerate 4 PCIe GPUs at once 😁
  • Versigial support for FinALI chipset, some registers for SiS496/7

Reply 2 of 8, by pc2005

Posted on 
User metadata
Rank Newbie
Rank
Newbie

s/Versigial/Vestigial

Reply 3 of 8, by BitWrangler

Posted on 
User metadata
Rank l33t++
Rank
l33t++

Interesting, the primary advantage appears to me thus far to be allowing games with a 486 friendly engine to be upgraded in resolution and modern monitor support.

Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.

Reply 4 of 8, by pc2005

Posted on 
User metadata
Rank Newbie
Rank
Newbie

Also the ability to boot CD/DVD and 32/128+ GB drive support.

Reply 5 of 8, by Many Bothans

Posted on 
User metadata
Rank Newbie
Rank
Newbie

If you need a guinea pig for SiS496/7 I'm more than happy to help. As charming as the AP43's AMI WinBIOS color themes are, it is limited in functionality and boot flexibility.

  • Zenith Z386SX-20, 8MB FPM, Video 7 1024i, Unhoused
  • AOpen AP43, Am5x86-133@160, 1MB L2, 128MB FPM, Stealth III S540 32MB Savage4, SB32
  • ITX-Llama, 3Dfx V3
  • Asus CUV4X-E, P3-933, 512MB PC133, Hercules 3D Prophet II MX 32MB, SB Live!

Reply 6 of 8, by pc2005

Posted on 
User metadata
Rank Newbie
Rank
Newbie
Many Bothans wrote on 2024-09-22, 19:45:

If you need a guinea pig for SiS496/7 I'm more than happy to help. As charming as the AP43's AMI WinBIOS color themes are, it is limited in functionality and boot flexibility.

Yeah eventually why not. The coreboot will probably need to be completely re-done as it barely fits in 128kB and it still missing SETUP (nvramcui would definitelly not fit).

But at the moment I'm too busy to even fix some bugs for UMC version 🙁.

Reply 7 of 8, by matze79

Posted on 
User metadata
Rank l33t
Rank
l33t

What PCIe Adapter to you use ?
Which Chipset does it have ?

https://www.retrokits.de - blog, retro projects, hdd clicker, diy soundcards etc
https://www.retroianer.de - german retro computer board

Reply 8 of 8, by pc2005

Posted on 
User metadata
Rank Newbie
Rank
Newbie
matze79 wrote on 2025-02-08, 23:21:

What PCIe Adapter to you use ?
Which Chipset does it have ?

Here with photos. It's PEX8111, the most common adapter. Some sellers are calling it PXE or 8112 or some combinations though. You need to solder an external 3.3V rail for PCIe connector and the chipset itself if you plan to use it on PCI motherboards which doesn't supply 3.3V, which is the most of 486 and pentium boards. Boards with ATX will most likely have 3.3V. I suggest to measure belonging pins on the PCI slot (external 3.3V connected to internal 3.3V would not make traces happy).

Go to top of page Go to top of page
Back to General Old Hardware
Close window
Close window