fsinan wrote on 2025-04-22, 19:54:

Hi, I couldn't find Cyrix 5x86-100 cpu jumper settings for M912 V1.7 board. Which settings would work? I have two of these boards one with AMI one with award bios.

https://theretroweb.com/motherboard/manual/am … 0c135064858.pdf

Page 6.

Nexxen wrote on 2025-04-22, 20:03:

fsinan wrote on 2025-04-22, 19:54:

Hi, I couldn't find Cyrix 5x86-100 cpu jumper settings for M912 V1.7 board. Which settings would work? I have two of these boards one with AMI one with award bios.

https://theretroweb.com/motherboard/manual/am … 0c135064858.pdf

Page 6.

Ah that slipped my check. Thank you!

Nexxen wrote on 2025-04-22, 20:03:

fsinan wrote on 2025-04-22, 19:54:

Hi, I couldn't find Cyrix 5x86-100 cpu jumper settings for M912 V1.7 board. Which settings would work? I have two of these boards one with AMI one with award bios.

https://theretroweb.com/motherboard/manual/am … 0c135064858.pdf

Page 6.

Didnt work with 073594 bios.

fsinan wrote on 2025-04-25, 10:57:

Nexxen wrote on 2025-04-22, 20:03:

fsinan wrote on 2025-04-22, 19:54:

Hi, I couldn't find Cyrix 5x86-100 cpu jumper settings for M912 V1.7 board. Which settings would work? I have two of these boards one with AMI one with award bios.

https://theretroweb.com/motherboard/manual/am … 0c135064858.pdf

Page 6.

Didnt work with 073594 bios.

Re: PC Chips M912 BIOS update for Am5x86 and Cyrix 5x86

does this work?

and this: Re: PC Chips M912 BIOS update for Am5x86 and Cyrix 5x86

fsinan wrote on 2025-04-25, 10:57:

Didnt work with 073594 bios.

Mind that M912 ver. 1.4 is a slightly different from ver. 1.7 (and subsequent newer update board revisions with fake cache "chips"). I don't know which board revision you have, but TRW link posted by Nexxen is for manual for M912 ver. 1.7 motherboard and it has some extra CPU settings jumper (JP34 and JP35 - these are missing on ver. 1.4 board). If I recall correctly JP35 is related to 4 V CPU setting, which is a Cyrix thing.

Nexxen wrote on 2025-04-25, 11:36:

Re: PC Chips M912 BIOS update for Am5x86 and Cyrix 5x86 […]
Show full quote

fsinan wrote on 2025-04-25, 10:57:

Nexxen wrote on 2025-04-22, 20:03:

https://theretroweb.com/motherboard/manual/am … 0c135064858.pdf

Page 6.

Didnt work with 073594 bios.

Re: PC Chips M912 BIOS update for Am5x86 and Cyrix 5x86

does this work?

and this: Re: PC Chips M912 BIOS update for Am5x86 and Cyrix 5x86

MY both mobo is 1.7. Anyway, I downloaded dual bios file for 1.7 from vogonsdriver library.

https://vogonsdrivers.com/getfile.php?fileid= … 675&menustate=0

Flashed it, ami bios was not stable and crashed thorough startup and benchs. But with Award bios, it seems stable and with max optimization of timings, it gives 316.7 sysinfo, 13.3 Quake score with cyrix boost by 5x86 command.

Adding photos and 5x86 parameters batch file that runs stable.

fsinan wrote on 2025-04-25, 14:05:

Have you tried to OC it @40mhz?

Nexxen wrote on 2025-04-25, 14:42:

fsinan wrote on 2025-04-25, 14:05:

Have you tried to OC it @40mhz?

Here it is;

fsinan wrote on 2025-04-25, 16:09:

Nexxen wrote on 2025-04-25, 14:42:

fsinan wrote on 2025-04-25, 14:05:

Have you tried to OC it @40mhz?

Here it is;

Your results are better than mine 😀

Nexxen wrote on 2025-04-26, 06:00:

fsinan wrote on 2025-04-25, 16:09:

Nexxen wrote on 2025-04-25, 14:42:

Have you tried to OC it @40mhz?

Here it is;

Your results are better than mine 😀

Probably cause of CHips&Tech VLBus graphic card. This card outperforms most of the cards out there. I'll test it in detail. Found it recently.

fsinan wrote on 2025-04-26, 06:42:

Nexxen wrote on 2025-04-26, 06:00:

fsinan wrote on 2025-04-25, 16:09:

Here it is;

Your results are better than mine 😀

Probably cause of CHips&Tech VLBus graphic card. This card outperforms most of the cards out there. I'll test it in detail. Found it recently.

I have a Cirrus 5428 VLB card. Well, it's nobody's fault we can't Quake @ 1080 60FPS 😀

fsinan wrote on 2025-04-26, 06:42:

Nexxen wrote on 2025-04-26, 06:00:

fsinan wrote on 2025-04-25, 16:09:

Here it is;

Your results are better than mine 😀

Probably cause of CHips&Tech VLBus graphic card. This card outperforms most of the cards out there. I'll test it in detail. Found it recently.

https://www.youtube.com/watch?v=Gp2Nzw0dH0U
Boosts available.
Cyrix 5x86 Register Enhancements Revealed
Praise feipoa 😀

I'm using register settings for 5x86.

Hey all, wanted to share a little something that may be helpful.

I have a M912 v1.7 board (possibly the Amptron version, idk) which came with AMI WinBIOS 12/01/1995. I noticed that the Turbo button doesn't work on that BIOS or the 12/02/1995X BIOS that some people use (only the Ctrl+Alt+Plus/Minus keyboard combinations work, and they seem flaky), and I just can't stand having a case with a non-working Turbo button, so I switched over Award with the J.2 patched BIOS.

Oddly, despite many folks reporting success with this BIOS (apart from the cosmetic issue with 5x86 speed detection), I actually experienced stability problems. Notably, I could not complete the extended memory test in Speedsys (crashing out with no message), and 3DBench would freeze a few seconds after showing a score. It looked like a memory problem, but swapping memory didn't seem to help. I also tried slower memory timings in the BIOS to no avail.

I started thinking about why this may have been happening, and realized that the source Award BIOS used for the J.2 patch is the 2.21R BIOS from the v1.4 board. v1.4 and v1.7 BIOSes are separate on The Retro Web, and possibly for good reason. On the AMI ones the POST string ends in GREEN or DGREEN for the v1.4 boards, but on v1.7 most end with GREEN-H or DGREEN-H. In addition, 2.21R uses the Award BIOS string contained "2C4X6B13" but the v1.7 Award BIOSes use "2C4X6H01". This suggests that the BIOSes are actually different to some extent and I probably need to use one specifically for v1.7. Unfortunately, the newest Award BIOS for v1.7 is from 11/03/1994 vs the v1.4 BIOS 2.21R from 09/08/1995, so it's a good bit older, so not exactly a good option and it would need modded to properly support 5x86 and writeback CPUs anyway.

So I decided to open both the v1.7 11/03/94 BIOS and the J.2 BIOS in Modbin and see if there were any settings differences. Turns out there were! There were a lot of differences in the auto tables. I'm not super knowledgeable in this yet, but I understand that the auto tables in particular are related to memory timings. I also noticed in the speed pin settings that the keyboard controller type for the '94 BIOS is KB-200X and the J.2 BIOS it's KB-200.

I went ahead and modified the settings in the J.2 BIOS to match the settings in the 11/03/94 BIOS. Running this, I'm no longer seeing the stability problems I had before, and can even push the memory timings up a bit successfully. I'm not sure if this was just a special "me" issue, but it seemed to help. I'm attaching my modified J.2 BIOS if anyone else with a v1.7 board sees similar issues and wants to try it.

Bonus, no idea if these are any good or not, but some benchmark scores with this BIOS, Am5x86@160mhz (4x40), 256k cache, 32MB 60ns FPM, and 2MB VLB Mach32 DRAM...
(BIOS settings: DRAM Wait State Select: 1WS, DRAM Page Mode: Fast, L2 Cache Read Wait State: 2-1-1-1, L2 Cache Write Wait State: 0WS, L1 Cache Update Scheme: Writeback)
NSSI: 71658 Dhrystones, 22578 Whetstones
3DBench 1.0c: 86.7
Topbench: 327
Speedsys: 59.99, Memory Bandwidth: 84.16 MB/s, L1: 128.36 MB/s, L2: 46.51 MB/s, Memory Throughput 28.89 MB/s
Doom demo3, max details: 2134 gametics in 1494 realtics = 49.99 fps
Quake demo1, max details: 15.4 fps (side note: on the WinBIOS, Quake runs extremely slow, scoring around 6.5-7.5fps depending on the memory settings, but all other benchmarks return "normal" results. I wonder why?)

Hi MrKsoft,

Thank you for your work on the M912 patch J.2 Award BIOS!

I believe the source 2C4X6B13 2.21R BIOS was found on an Amptron DX-6900 board, which is an M912 clone. Although the “B1” manufacturer ID in this BIOS indicates “BEK-Tronic Technology”, instead of “H0” for PC Chips (Hsin Tech), I wasn’t worried because there are so may PCChips clones out there.
TRW indeed lists this 2C4X6B13 BIOS for v1.4 boards only, but it is the latest M912 Award BIOS and the best candidate for my patched versions.

As several Vogons members had success with the patch J.1 and J.2 BIOS on different board revisions, I was hoping that the patched M912 BIOS could be used on both v1.4 and v1.7 boards.
I therefore read your experiences with the v1.7 board with interest, and downloaded your adapted M912_J2M BIOS and looked at the changes you made.

The Auto Table menu in Modbin is indeed all about memory, L2 cache, and ISA-bus clock timings for each FSB speed. The BIOS uses this chipset register programming when Auto Configuration is Enabled (CHIPSET FEATURES SETUP menu).
The settings you used from the older 2C4X6H01 BIOS mainly relax the memory timings, so this could explain the better stability. However, you wrote that you manually tried slower memory timings to no avail. So I’m puzzled how the slower Auto Config timings could have helped. 😉

Anyway, I will test your M912_J2M BIOS on my UMC498 board, and compare it to the final M912 patch J.3 BIOS I’m presently working on.

Thanks again, Jan

Thanks for the info, Jan.

My modifications may just be a placebo. It's hard to tell. I've been doing a build with this board but as I've built it up I've started to run into more issues without a clear cause, such as my "test bench" CF no longer booting despite being identified correctly and readable with a boot floppy, floppy drive boot seek sometimes failing or going too fast (not sure if the drive yet), and the Turbo LED stopped working at some point while the Turbo function itself still works. It's possible that I'm seeing some degradation due to the board needing some service, that the freezing was a warning sign, and that my BIOS mods just masked the issues and kicked the can down the road a bit. I am investigating this.

Other v1.7 owners may want to try the unmodified J.2 BIOS and see if my issues can be recreated or if I'm the odd one out.

isn't there a MR-BIOS for this board? How would that compare with the AMI and Award that came with the board and have been patched in this thread?