retro games 100 wrote:

Re: PSU. That's very interesting. I wonder, is this problem due to the ADZ architecture, or is the PSU an important factor? Could it be a combination of the two? I wonder which issue is more pertinent, the ADZ or the PSU?

My theory is that the later the manufacturing date of the AMD 5x86, the better the chances for a successful overclock to 200Mhz.

The 145W PSU is of a good brand, FSP (one of my favorites actually).

I've seen those soldered jumper shorts myself on a couple boards, but this may not mean that the board is unable to properly support the disabled FSB speeds that are blocked by the "hardwiring" of any particular jumper.

The 5x86's with the last production dates are not even marked as ADW or ADZ, they are usually laser marked.
Afaik they were produced well into 1998!

What is the latest bios for MB-8433UUD rev. 2 and where can I find it?

@udam_u

I have attached two SST BIOS versions, one from March 26 1996, the other from May 20 1996. Use at your own risk. If your BIOS chip has a ~7 mm hole on the top, you cannot flash it as far as I know. You may even ruin the BIOS.

I have a version 3.0 board without the eyelet, but March 26 1996 is the latest for the Intel-style update. I have read reports that setting JP13 to the SST setting for an Intel-style BIOS allows you to update to the SST, May 20 1996 BIOS, but I am not going to risk this.

Thank you feipoa! I wasn't able to find this bios on the internet. Unfortunately bios on my motherboard has this small window. Have you ever removed award sticker from your bios? If so, what is typed on it? Maybe I can find the same part on one of my damaged motherboards... ^^

UV-erasable EPROMs (the "small-windowed" chips) cannot be reprogrammed using "regular" utilities like AWDFLASH, UNIFLASH and so on... I recently managed to ruin the BIOS of a 486 PCI board this way (somehow the utility managed to erase something, but failed to complete the flashing process) - I had to replace it with an EEPROM (electrically-erasable) that I hot-flashed in another board.

Regarding these older style UV BIOS chips - the ones with the "little window" on them - first, they need to have their contents erased using a UV eraser device, and then second, your chosen BIOS file needs to be programmed in to them, using a BIOS programmer. The mobo cannot do this programming for you.

Typically, if you do not have a UV eraser device, and also a BIOS programmer device, you contact a "bios repair dude", who will do this service for you. Optionally, you can send them your BIOS chip. This might save you a small amount of money. Also, this step will be required, if the "bios repair dude" does not have a suitable BIOS chip in stock. I did this process fairly recently, and it was successful. Good luck! 😀

Thanks guys! (:
The idea of sending chip to "bios repair dude" 😁 is good but maybe I have the same EE Flash as feipoa on one of my few damaged motherboards. If so, it would be cheaper to use EE flash+awdflash+motherboard than "bios repair dude" 😁 service.

BTW
I heard that you can erase UV-erasable EPROMs by long exposure to the sun. ^^

I've heard it would have to be a _really_ long exposure 😀 weeks, that is...

iulianv wrote:

I've heard it would have to be a _really_ long exposure 😀 weeks, that is...

Get one of these 😁

iulianv wrote:

I've heard it would have to be a _really_ long exposure 😀 weeks, that is...

Tetrium wrote:

Get one of these

He he he ok, so I'll ask for help my friend who goes often to solarium or I'll take it when I go on vacation! 😁

@feipoa
How i can overclock the IBM 5x86 on a PcChips m919 v 3.4 b/f
i try with 5V and 2x 66 multiplier but
it gets stuck at "133 MHz CPU Clock"

I haven't had any long-term success overclocking Cyrix 5x86 cpus. I have even attempted overclocking a Cyrix 5x86-100/4X at 33.3 x 4 = 133 and it would run for about 5 minutes worth of benchmarks, then hang at the DOS prompt.

The Cyrix 5x86 literature warns against running at voltages outside of 3.45 +-0.15, but this may be a direct factor of a passive heatsink designed by Cyrix for the CPU. I tend to run the Cyrix 5x86 at 3.70 volts without issue using a thermal paste and fan.

From my experience, the Cyrix 5x86-80 seems to have better luck overclocking to 100 Mhz than the 5x86-100 does at 133 Mhz. If you want to overclock a 5x86-100, I would start with running it at 3 x 40 Mhz (120 Mhz).

What is the stepping/revision of your 5x86-100? If it is the IBM model with the blue anodized aluminum heatsink, you can attach a 486 fan to the top of it. If you have an IBM 5x86 100HF, this might really be a 120 Mhz part, but even if so, I haven't gotten past the initial boot screen at 133 Mhz.

My CPU is the IBM 5x86C 3v3 with the blue heatsink, but i attached a fan for OC
the chkcpu "steppings" are:
DIR0:2Dh
DIR1:05h

Maybe i must change some BIOS settings, or pcchips mobo or cyrix CPU is the problem?

Note: When i try to overclock to 3x50=150 with 5v i dont see the BIOS post

PS: I have three BIOS flash files dated 05/06/1996, 10/16/1996 & 09/14/1998
now i use the 1996 versions

Sorry for my "Cheap" english

DIR1=5h is Stepping 0, Revision 5. Make sure you don't enable branch prediction. All Cyrix 5x86-120/133 CPUs I've seen have been stepping 0, revision 5, and most Cyrix 5x86-100/3X cpus have been stepping 1, revision 3, although the ones produced in the first 2 months of 1996 tend to be Stepping 0, Revision 5.

Are these flash BIOSs for the PCChips M919? Can you attach them along with the flash utility used to update the BIOS?

Do you happen to have the flash BIOS revision history for the BIOSs as well?

Thanks.

How i can enable or disable Branch Prediction? i dont see any BP option in the BIOS
The Bios files are for the M919, and the utility for flash is Uniflash, now i cant attach the Bios but in a few hours or tomorrow i attach the files+flash application and as a extra the "Unofficial M919 v 3.x manual"
My 5x86 run at 40x3 and 60x2
PS:The M919 bios is a "WinBios", and this mobo needs a flash-able Bios chip
You can post a picture of the m919 best BIOS settings for 60x2 =120 Mhz?
The Quake 1 timedemo demo1 gives me 12.8 fps

sebaz_ri, you will need to adjust the Cyrix 5x86 features in software if they are not provided in the BIOS. If you are using the M919, you have support for Linear Burst and LSSER already. You'll want to enable those.

There are a few people and companies out there who have made programs to enable the the extra Cyrix 5x86 features. A good starter is the Peter Moss Utility. Refer to the attachment. Others are made by Evergreen, IBM, and Rodney - CyrixGo.

Are you running the 1998 BIOS for the M919? I wonder if it corrected problems with AMD L1 WB cache and SCSI bus mastering? Or fixed bugs associated with some VLB graphics cards? I am looking forward to testing out these BIOS versions. All the Google sites where I was able to find the latest BIOSs have inaccessible links.

EDIT: Your Quake timedemo1 score looks slow. What cache and RAM settings are you using? Try 2-1-2 and 0/0. For which Cyrix enhancements to enable, refer to The Ultimate 486 Benchmark Comparison, link here,
The Ultimate 486 Benchmark Comparison

All tests here were done on an M919 board with the specified Cyrix 5x86 enhancements enabled. Your scores for 120 Mhz should be similar.

Note: For update the BIOS i recommend you made a backup image of the current BIOS and disable TURBO

My BIOS settings are 2-1-1-2 2/2 WS because when i set to 0/0 or 1/1 Quake crashes
Also the slow FPS maybe is because i have only 8 mb of ram and i dont have L2 cache
The video card is 2 MB
From where i can download 3D mark 99 MAX?
The 3dbench 1.0c gives me 66.6 FPS

Which BIOS Version are you using? Have you noticed any loss of features from the 1998 BIOS compared to the May 1996 BIOS? Any problems going back and forth between them?

I suspect that no L2 cache, and 2WS/2WS explains the low Quake score.

You should be able to download 3DMark99Max from here after hassling with the advertisements.
http://www.ausgamers.com/files/browsegame/html/10/49

I use the 1996 versions because one of my video cards dont work with the 1998 version, but i tried the 1998 BIOS with other cards and work fine
Now i enabled LSSER and Linear Burst and Quake timedemo demo1 gives me 13.5 FPS
Why i cant set Wait States to the most aggresive settings?
PS:You downloaded the attached files?

What video card had trouble with the 1998 BIOS?

You probably can't set the most aggressive wait states because you are using slower RAM, like 70 ns RAM. Try 60 ns EDO or FPM RAM.

If you don't have any L2 cache, you probably won't get up to 16.4 fps. What video card are you using?

Yes I downloaded the BIOS files. Thank you. I haven't had time to test it out yet. I have been working on my Cyrix 5x86-133 stability project.

I have three video cards:
1-Alliance ProMotion AT 24 Pci 2 mb
2-Trident 9685 Pci 2 mb
3-Cirrus Logic CL-GD 5434 Pci 1 mb

The video card 1 is the 1998 problematic card
With the other 2 cards i dont found 1998 problems

Now im using the video card 1

PS:You also download Bios documentation and M919 manual, or just BIOSes and flash program?
From where i can download MDK DOS Benchmark?
And what are your M919 suggestions
Thanks for all! feipoa