I had a similar case recently and the culprit was a faulty capacitor.

I guess I'll order in the parts for a re-cap then. Joy. Thank you though!

On slot A motherboards, caps usualy. If the caps look ok, run also memtest and check if agp fast write is disabled.

paradigital wrote on 2023-05-09, 12:51:

Does anyone have a list of "best" drivers to try?
Thanks in advance!

Is my hardware compatible with smoke.dll of Microsoft?
This hardware is 20+ years old.
Always start by replacing electrolytic capacitors. Even if they look "fresh, just from the factory"
Then they check the power supply of the AGP - 3.3 / 1.5V, replacing the same capacitors or transistors.
At that time, engineers used very strange solutions.

bogdanpaulb wrote on 2023-05-09, 13:12:

On slot A motherboards, caps usualy. If the caps look ok, run also memtest and check if agp fast write is disabled.

It's actually quite common on old boards to see caps that look OK at first glance, but are in fact dead.

By 'if the caps look ok' i didn't meant only optically and thou i completely agree with you, most people don't have a capacitor tester and the skills to take them out and test them (some don't even have a multimeter to check for a Vdrop).

bogdanpaulb wrote on 2023-05-09, 13:56:

By 'if the caps look ok' i didn't meant only optically and thou i completely agree with you, most people don't have a capacitor tester and the skills to take them out and test them (some don't even have a multimeter to check for a Vdrop).

No problem, just wanted to point this out again, because it's a very common misconception.
PS: salutari din Brasov! 😁

Fortunately, I have both a decent desoldering station, soldering iron, hot-air station, and a decent multimeter, though not a cap tester/esr meter.

I'll order the relevant caps tonight and fingers crossed it'll resolve the issues. I need to re-attach an SMD cap on the Geforce 256 anyway, someone has done a previoulsy dodgy looking repair.

paradigital wrote on 2023-05-09, 12:51:

I know that Irongate boards can be finicky at the best of times, but I'd have thought it would be more stable than 30s to 30 mins uptime.

That's actually not my experience with them at all!
Granted, I think I only have multiple boards of the same make/model (4 x Gigabyte 7IXE) based on this chipset, but they are almost as solid as the 440BX boards (well, they are a bit finicky when it comes to memory compatibility, they outright refuse to POST with certain RAM modules). But once you find a compatible RAM kit and they POST, they just work.

Do you see random crashing, even when idling on the desktop? Or does it only happen in games/3D apps?
You mentioned that you replaced many components, but what about the CPU? Are you 100% sure that it's healthy (and temps are good)?
Even though replacing the caps is definitely something worth doing, I would first try and eliminate other potential factors.

bloodem wrote on 2023-05-09, 14:50:

That's actually not my experience with them at all! Granted, I think I only have multiple boards of the same make/model (4 x Gig […]
Show full quote

paradigital wrote on 2023-05-09, 12:51:

I know that Irongate boards can be finicky at the best of times, but I'd have thought it would be more stable than 30s to 30 mins uptime.

That's actually not my experience with them at all!
Granted, I think I only have multiple boards of the same make/model (4 x Gigabyte 7IXE) based on this chipset, but they are almost as solid as the 440BX boards (well, they are a bit finicky when it comes to memory compatibility, they outright refuse to POST with certain RAM modules). But once you find a compatible RAM kit and they POST, they just work.

Do you see random crashing, even when idling on the desktop? Or does it only happen in games/3D apps?
You mentioned that you replaced many components, but what about the CPU? Are you 100% sure that it's healthy (and temps are good)?
Even though replacing the caps is definitely something worth doing, I would first try and eliminate other potential factors.

My old GA-71XE4 was also a great board, but that was when brand new!

I don’t currently have another Slot A CPU to test, though I am waiting for a 700 to arrive. The temps seem OK using the tried and tested “finger on heatsink, can you keep it there for 15s” test. I have already dismantled the cartridge and replaced the TIM, so we should be good there, if the CPU is indeed fine.

The crashing can be literally any time, opening the Start Menu, browsing Explorer, installing an application, etc.

I'd use the TNT2 until you get it completely stabilized because GeForce cards don't like Slot A chipsets. Something more sedate than a TNT2 Ultra would probably be ideal.

How much +5v current does your PSU provide? This is an Athlon 900 so that is something to look at. You probably want at least 30A.

32A on 5v.

I could use one of my Voodoo 3s, but I’m really wanting to use the GeForce 256 DDR.

paradigital wrote on 2023-05-09, 16:55:

I don’t currently have another Slot A CPU to test, though I am waiting for a 700 to arrive. The temps seem OK using the tried and tested “finger on heatsink, can you keep it there for 15s” test. I have already dismantled the cartridge and replaced the TIM, so we should be good there, if the CPU is indeed fine.

The crashing can be literally any time, opening the Start Menu, browsing Explorer, installing an application, etc.

An oscilloscope would be very useful at this point, it's very likely that, if caps are indeed to blame, you would see a ginormous voltage ripple (which could explain the instability).
If you don't have an oscilloscope, you could also start by checking the CPU voltage with a multimeter. Again, if capacitors are damaged, it's very likely that VCORE is below what it should be (failed capacitors often turn into pseudo-resistors).

I was just writing about a scope and probe on the 4 caps on the vrm 5v power in and on vcore also, try and check for system stability with a weak pci video card (2mb) if you have one.

Unfortunately no oscilloscope in my arsenal, I’ve got good quality fluke meters though.

Plenty of low end PCI video cards I could throw in however.

paradigital wrote on 2023-05-09, 12:51:

MSI MS-6191 (AMD 750 Chipset)
Slot-A Athlon 900

Which exactly Slot A model you have? Is it Orion or Thunderbird?
Some Slot A motherboards don't work properly with Thunderbirds.

I’m pretty sure it’s a Tbird as I seem to remember the model is a A0900, not a K7900.

The 700 that I’ve got en route is a Pluto.

I'd use that Voodoo 3 to make sure it's not the GPU + AMD 750 that's causing these issues. You should approach this chipset like one does with VIA chipsets.

it's very very easy to damage Duron/ Athlon CPU Core, while installing a cooler