Chadti99 wrote on 2025-09-17, 00:28:

feipoa wrote on 2025-09-16, 23:46:

Chadti99 wrote on 2025-09-16, 20:56:

I ended up sourcing another m919 and this one seems to be quite a bit more stable although still inconsistent between boots.

That sounds like the majority of M919's. Maybe it's related to their thin and springy motherboards.

Agreed, you’ve warned me a few times. So far I got through a Windows install no problem but crashes when it finally boots to the desktop. I should really give up on this board.

I also tested the 1:1 pci thing recently with my 180 setup and no go. I used cards that have proven to work at a 60+ mhz bus on other boards previously. My matrox g200 would make it as far as dosbench after being hot switched and then freeze shortly into anything, my sis 6326 wouldn't even make it that far. I suspect they would if I relaxed cache timing....however experience tells me that the loss of speed from relaxing cache is not worth faster pci, so I'm not pursuing the 1:1 avenue any further

Do you have the same crash after windows install /desktop even if you slow down to 180? Also, if you run the quake benchmark from dosbench at 640x480 does it complete, or does it crash? Because if it crashes that just means that cpu won't run 200 reliably

Edit: one more thing if pursuing windows on these- I found both with the matrox card AND with a cl gd5464 laguna VGA card I was using I would have to turn off bus mastering in the driver's (and usually had to use the manufacturers driver for this as the windows one didn't offer it). If i did not, there would be trouble.

i looked at old notes early in this thread and it looks like i was able to run the board at 3x60 1:1 tightest bios timings. results confirm it with the high doom score.
however i was not able to get it stable at 3x66.
so your success is encouraging, may give that a try locally.

so bertram, are your running fully stable 3x66?

this board equipped with the modern 1mb L2 cache module is great for 3x60. probably the best one out there for DOS interactive graphics, but pci divider must be 1:1.
it is somewhat less than ideal for Windows because it is unable to run some specific pci graphics cards such as voodoo3 that offer peak perf in win gui and enable 3d accelerated graphics.

Am I the only one who runs this board with VLB graphics + Voodoo2? This saved me a lot of PCI graphics grief. ARK1000VL with modified MCLK and updated RAMDAC was the winner for me, along with 50/60 ns TSOP EDO modules.

Love the idea, I’d like to do a similar setup, maybe just not with the M919 board 🤣, we’ll see.

“ ARK1000VL with modified MCLK and updated RAMDAC was the winner for me”

I’ve def tried the ARK, it needs 1ms wait state at 50MHz and wouldn’t post higher. Although I think it beats the 33MHz PCI in most dosbench tests.

Tell me more about this modified MCLK and updated RAMDAC.

pshipkov wrote on 2025-09-17, 05:23:

so bertram, are your running fully stable 3x66?

I couldn't find any issues at 3x66 EXCEPT the freezing at the "windows is shutting down" screen, which does not happen at 3x60. No apparent problem on restart. However, while I do enjoy building and messing with these I don't particularly enjoy registry issues that this may eventually to on a daily driver, hence me running it at 3x60 for normal use.

Perhaps I should add - I run this on an old plug converted ATX power supply that I upgraded some capacitors in to larger values. I also have an extra 100uf (I think) cap slapped on the back of the cache module. In open bench testing this made no apparent difference (the initial setup being done on an old AT supply), however my thinking is some better filtering and perhaps tighter voltage regulation definitely can't hurt when running other components at their limits

bertrammatrix wrote on 2025-09-17, 16:27:

I couldn't find any issues at 3x66 EXCEPT the freezing at the "windows is shutting down" screen, which does not happen at 3x60. No apparent problem on restart. However, while I do enjoy building and messing with these I don't particularly enjoy registry issues that this may eventually to on a daily driver, hence me running it at 3x60 for normal use.

The freezing at the “windows is shutting down” screen isn’t upan unusual thing for me. Some builds do it, others don’t. I thought it might be driver related. Shut down to DOS always works though.

Win 98SE hangs on shutdown

feipoa wrote on 2025-09-17, 09:44:

Am I the only one who runs this board with VLB graphics + Voodoo2? This saved me a lot of PCI graphics grief. ARK1000VL with modified MCLK and updated RAMDAC was the winner for me, along with 50/60 ns TSOP EDO modules.

Very cool setup indeed (cannot find where you documented the build r.n.).
For various reasons i find VLB cards more interesting than PCI ones, not only graphics ones but also local storage controllers.

douglar wrote on 2025-09-17, 22:25:

The freezing at the “windows is shutting down” screen isn’t upan unusual thing for me. Some builds do it, others don’t. I thought it might be driver related. Shut down to DOS always works though.

Win 98SE hangs on shutdown

I think he mentioned that the issue is gone at 3x60, so it is a side effect from further overclocking.
I would keep the 3x66 as the whole shutdown/restart cycle in these early Windows versions didn't provide a whole lot really.
Often it ends at static screen asking you to manually power-down or restart.

pshipkov wrote on 2025-09-18, 20:42:

I think he mentioned that the issue is gone at 3x60, so it is a side effect from further overclocking. I would keep the 3x66 as […]
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douglar wrote on 2025-09-17, 22:25:

The freezing at the “windows is shutting down” screen isn’t upan unusual thing for me. Some builds do it, others don’t. I thought it might be driver related. Shut down to DOS always works though.

Win 98SE hangs on shutdown

I think he mentioned that the issue is gone at 3x60, so it is a side effect from further overclocking.
I would keep the 3x66 as the whole shutdown/restart cycle in these early Windows versions didn't provide a whole lot really.
Often it ends at static screen asking you to manually power-down or restart.

That’s curious. I see it more on faster computers. Maybe it’s a timing thing? I feel like it’s only bad if windows wants to doc a scan disk on the next power up. If it doesn’t, I feel like the system shutmdown successfully except for showing the final graphic.

I assume so too, but don't remember hitting this problem myself so far, so only can rely on other's feedback and results to reason how late in the shutdown/restart process the hang occurs and if this causes any corruption.

Btw, linked bertrammatrix and chadti posts in the directory on the first post in this thread.

Whether a hang on Windows 9x shutdown is timing related is an interesting question. I had some installations which didn't like certain display drivers and these drivers seemed to trigger this error, but only at certain FSBs (IIRC). I think 33 Mhz didn't have the error, but 40 MHz FSB initiated the error. I eventually swapped out the graphics card and the issue resolved.

However, on my M919, at 180 MHz, with the ARK1000VL, 2-1-2 sram and 1/0 dram ws, I almost always get a hang on shutdown of Win 95c. It can be a bit of an irritant, so leave a text file on the desktop with a reminder in the filename to 'restart to DOS on shutdown'. There are no other stability issues with this system.

I would be interested to know if 'restart to DOS' on bertrammatrix's 3x66 M919 resolves his issue. If it does, and this is the only stability concern, I'd stick with 3x66.

chadti99, the RAMDAC/MCLK mod can be found here: Where to obtain 110 MHz RAMDAC for ARK1000VL graphics card? - in short, swap to a faster RAMDAC to unlock faster memory clock speeds. Then remove MCLK setting resistors with jumper headers to play with your MCLK. The faster RAMDAC and MCLK should also open 800x600x24bit non-interlaced. If you want to also unlock 1280x1024x256c at 60 Hz non-interlaced, implement mkarcher's VGABIOS mod. Use the official ARK resolution/depth/refresh Win9x app, otherwise the default Windows 95 Display Properties may get stuck on interlaced mode for some resolutions.

feipoa wrote on 2025-09-21, 08:56:

I would be interested to know if 'restart to DOS' on bertrammatrix's 3x66 M919 resolves his issue. If it does, and this is the only stability concern, I'd stick with 3x66.

I think ("think" because, well, m919 - no certainty here) I solved the shutdown hang at 3x66!

The discussion here prompted me to spend some more time trying to get to the bottom of it. I think initially I was so excited about everything running fine at 180 that I just didn't tweak enough to achieve full stability at 200, I had just assumed that I had hit the brick wall.

What did I do? Well, yesterday I tried the "restart to dos" while running at 200, and it worked, no problems after. Being comforted by this I went on to play AOE2 at 1024x768. I got a crash to desktop about an hour in....hmmm, we need more voltage I'm thinking! I pulled the resistor jumper to go from 3.66v to 4v on the fly and went to play again- couldn't make it crash. Afterwards shut down (not to DOS) and to my astonishment- no more shutdown hang!

Since I typically don't like to run a CPU at more then absolutely necessary, I hooked up a multi turn potentiometer instead of my resistor jumper and was eventually able to trim the voltage down to roughly 3.85v, which is about 0.1v higher then the last voltage where I was still able to replicate a problem. I am much happier with this then with 4 volts (especially because of the cache). If this voltage proves to be stable in the long term I will likely replace the pot with resistors.

Sounds about right - fine tweaking to get over the finish line.
I think you got a magical cpu there. 200mhz, 3.8v, passive cooling.
If you manage to get the pci bus at 1:1 or some fast vlb graphics card, you will probably get the fastest system out there.

More time will tell. Give it a year. Sometimes you run across a system for which the shutdown error occurs only 1 in every 10 sessions. Small variations in room temperature can do wonders or be your enemy.

Great news Bertrammatrix!

I need to try tweaking the voltage in my cpu, I’m sure it would be happier just a bit below the 5v it requires currently.

I think the crashing I’m seeing in windows is related to the pci storage controller I’m using a tx2 100 I think.

Can you share what exact model storage controller you are using? Would love to attempt to replicate your setup.

Chadti99 wrote on 2025-09-21, 23:05:

Great news Bertrammatrix! […]
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Great news Bertrammatrix!

I need to try tweaking the voltage in my cpu, I’m sure it would be happier just a bit below the 5v it requires currently.

I think the crashing I’m seeing in windows is related to the pci storage controller I’m using a tx2 100 I think.

Can you share what exact model storage controller you are using? Would love to attempt to replicate your setup.

I also use a tx2 100. I have 2 different revisions but didn't seem to make a difference.

What video card are you using? If it is anything that is bus master capable-that feature will likely have to be turned off if at all possible, I'm not sure if it's the motherboard or the tx2 (I've never used anything else on this) but bus master on the VGA is always trouble with this combo

bertrammatrix wrote on 2025-09-22, 01:02:

Chadti99 wrote on 2025-09-21, 23:05:

Great news Bertrammatrix! […]
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Great news Bertrammatrix!

I need to try tweaking the voltage in my cpu, I’m sure it would be happier just a bit below the 5v it requires currently.

I think the crashing I’m seeing in windows is related to the pci storage controller I’m using a tx2 100 I think.

Can you share what exact model storage controller you are using? Would love to attempt to replicate your setup.

I also use a tx2 100. I have 2 different revisions but didn't seem to make a difference.

What video card are you using? If it is anything that is bus master capable-that feature will likely have to be turned off if at all possible, I'm not sure if it's the motherboard or the tx2 (I've never used anything else on this) but bus master on the VGA is always trouble with this combo

Was using a Riva128, I think there is something wrong with the drivers I'm trying to use with Win98. Any chance you could share the driver files you have?

Chadti99 wrote on 2025-09-27, 16:16:

bertrammatrix wrote on 2025-09-22, 01:02:

Chadti99 wrote on 2025-09-21, 23:05:

Great news Bertrammatrix! […]
Show full quote

Great news Bertrammatrix!

I need to try tweaking the voltage in my cpu, I’m sure it would be happier just a bit below the 5v it requires currently.

I think the crashing I’m seeing in windows is related to the pci storage controller I’m using a tx2 100 I think.

Can you share what exact model storage controller you are using? Would love to attempt to replicate your setup.

I also use a tx2 100. I have 2 different revisions but didn't seem to make a difference.

What video card are you using? If it is anything that is bus master capable-that feature will likely have to be turned off if at all possible, I'm not sure if it's the motherboard or the tx2 (I've never used anything else on this) but bus master on the VGA is always trouble with this combo

Was using a Riva128, I think there is something wrong with the drivers I'm trying to use with Win98. Any chance you could share the driver files you have?

I don't have any drivers for a riva 128, and the promise just uses the usual win98 driver, no alchemy there. You should check out Feipoa's thread "modern graphics on a 486". Unfortunately some video cards just won't work properly under windows as there were no versions of drivers for them that work on 486 CPUs- they require a Pentium (or at least a POD on socket 3) to work properly, or, they may only work with one certain CPU with one particular driver (ie a driver that works with a Cyrix 5x86 may not work with a am5x86), I can confirm Riva TNT2 being like that, so I'd suspect the 128 may have the same issues. And again, of these video cards that MAY work on the 919 some will require bus master being turned off (which the driver may not allow), which may make them unusable under windows.

pshipkov wrote on 2025-09-21, 19:42:

Sounds about right - fine tweaking to get over the finish line.
I think you got a magical cpu there. 200mhz, 3.8v, passive cooling.
If you manage to get the pci bus at 1:1 or some fast vlb graphics card, you will probably get the fastest system out there.

I think the CPU may indeed be magical, however the motherboard is not. Long term stability at 66mhz is an issue. I was able to recreate crashes to desktop by playing Blood for 30-40 minutes and heat-soaking the system. This would occur long after full cpu warmup. Setting voltage higher didn't help, as did not using a separate regulator for the cpu and setting the cache voltage at 3.3 volts (I'd rather not run it at 4 volts). I did not try additional cooling, but open case made no difference, around 20° Celsius here, so unlikely it would do much unless ambient temperature went lower. Though the crashes were benign and would not freeze the system (and I couldn't make any crash happen by playing windows based games) after a random restart I had this weird thing happen when the HDD would just keep spinning up, ie as if it was getting reset commands. This went away after a bit of a cooldown. Subsequent tests back at 180 / 3.6 volts- zero issues.

I am still perfectly happy with 180, even with there being a noticeable difference at 200 which is seemingly "within reach". I should probably stop tormenting this setup while it is still working (or, should I? ) 🤣

It does kind of make me wonder though, if it really is the motherboard that is the limiting factor here, how fast could this CPU actually run (hot433 75mhz fsb??). I remember seeing a pic of someone's POST screen at 225mhz (unsure of exact #), suddenly this doesn't seem so far fetched from reality if one has a good sample CPU

feipoa wrote on 2025-09-17, 09:44:

Am I the only one who runs this board with VLB graphics + Voodoo2? This saved me a lot of PCI graphics grief. ARK1000VL with modified MCLK and updated RAMDAC was the winner for me, along with 50/60 ns TSOP EDO modules.

As an owner of a voodoo2 I would if I had an ARK 1000 pop up that didn't cost an arm and a leg