Possibly a bad memory chip or cracked solder joint if you're lucky.

I've had something similar happen on my n64 (while playing) and it was a solder joint that had cracked clean through but the damage could only be confirmed under a microscope.

I've tested all the soldered on parts with a multimeter and there are 3 positions that don't conduct electricity: C27, C236 and C235. They're near the PCI connector on the back of the card.

Those are probably diodes; you won't see continuity on them with a multimeter.

It's probably a bad memory chip or a cracked solder joint. And if it's a cracked joint you wouldn't be able to find it without the aid of a microscope.

Did the card work with this processor before you had this problem?
I have had the same issue on my PC, but it worked just fine on a mmx233.

C means capacitor; capacitors should NOT conduct electricity

keenmaster486 wrote on 2021-08-02, 21:06:

C means capacitor; capacitors should NOT conduct electricity

That makes it even worse.

Aebtdom wrote on 2021-08-02, 20:59:

Did the card work with this processor before you had this problem?
I have had the same issue on my PC, but it worked just fine on a mmx233.

This problem is reproducible on all of these CPU configurations:
- 2x SL6BY @ 700MHz
- 2x SL6BY @ 1000MHz
- 2x SL6BY @ 1200MHz
- 2x SL4C8 @ 1000MHz
- 2x SL4C8 @ 500MHz
- 1x SL4C8 @ 1000MHz
- 1x SL4C8 @ 500MHz

Important to note is that sometimes the 3dfx logo can render and pass, but the rest of the game will hang FreeDOS.

This possibly could be due to using the Voodoo Graphics card with a very fast CPU since the card is CPU speed sensitive. Do you have a much slower system to check if the issue is there?

Gmlb256 wrote on 2021-08-03, 16:57:

This possibly could be due to using the Voodoo Graphics card with a very fast CPU since the card is CPU speed sensitive. Do you have a much slower system to check if the issue is there?

Indeed. Those CPUs are way too fast.
The Voodoo 1 should always be tested on very slow CPUs (personally I wouldn't go beyond a Pentium 2 266, preferably a Pentium MMX). I mean... this card is slow anyway, it will severely bottleneck even faster Pentium MMX CPUs.
Even though it can work on certain faster platforms when all the stars align, if it doesn't... the results will be inconclusive.

And those kinds of artifacts are usually the 'normal' behavior with fast CPUs.

That's exactly the same effect I got with my Voodoo1 and an Athlon XP or any Athlon above 500mhz, it would work fine most of the time at 500mhz.
I found it was worse with a Barton core chip with 512k cache.
Try a slower celeron if You have one.

I had to do a repair on a Voodoo 1 today that I had ordered form eBay. Some of the pins that had broken away from their solder joints and the card needed to be repaired.

My card is working fine with a Pentium 3 SL35D clocked at 300Mhz; 66mhz bus x 4.5 is the fastest this motherboard will go without increasing the bus speed. i had an issue with stability while setting up this system with a Banshee that ended up being due to a bus overclock. Are you overclocking at all?

A friend of mine just helped a lot - we swapped the positions of RAMs and this had the effect of the colors being changed - green turned into orange.

It's important to note that the Voodoo 1 model I have has been identified as Guillemot Maxi Gamer 3D. We've ordered replacement RAMs and gone the extra mile of ordering SOJ 40 pin sockets to make it a lot easier to replace RAM in the future.

Edit: the reason why I'm overlooking suggestions of slowing down the CPU is that this card worked reliably even on 1.4GHz dual Tualatins all the time. Now it reliably fails. I'll give that option a go if the new memories fail.

moog wrote on 2021-08-06, 09:33:

A friend of mine just helped a lot - we swapped the positions of RAMs and this had the effect of the colors being changed - green turned into orange.

It's important to note that the Voodoo 1 model I have has been identified as Guillemot Maxi Gamer 3D. We've ordered replacement RAMs and gone the extra mile of ordering SOJ 40 pin sockets to make it a lot easier to replace RAM in the future.

Wait.... what?! Did you even read what we said? 😀
Try a much slower CPU! That behavior (apparent artifacting) is typical for a Voodoo 1 running on fast CPUs.

moog wrote on 2021-08-06, 09:33:

Edit: the reason why I'm overlooking suggestions of slowing down the CPU is that this card worked reliably even on 1.4GHz dual Tualatins all the time. Now it reliably fails. I'll give that option a go if the new memories fail.

I actually mentioned in the previous post that IT CAN sometimes work with faster CPUs when all the stars align. However, testing it on a fast platform and assuming from the get-go that it's dead is a bad way to do it. 😀
Also, testing AFTER replacing the VRAM chips will add a new variable to the mix. 😉
Anyway, suit yourself.

bloodem wrote on 2021-08-06, 09:40:

I actually mentioned in the previous post that IT CAN sometimes work with faster CPUs when all the stars align. However, testing it on a fast platform and assuming from the get-go that it's dead is a bad way to do it. 😀
Also, testing AFTER replacing the VRAM chips will add a new variable to the mix. 😉
Anyway, suit yourself.

I must be very lucky then because the stars kept aligning all the time until a few weeks ago 😁

moog wrote on 2021-08-06, 09:53:

I must be very lucky then because the stars kept aligning all the time until a few weeks ago 😁

Are you sure that nothing changed since you last tested it? Was it working before on the same motherboard, same CPU(s)? Did you reinstall the OS since then? Did you add other peripherals/cards? Did you install other new drivers? Any slight change could give you different results.
You have to understand, this card and its drivers were never meant to run on such powerful CPUs.
What I can tell you is that I've had those exact artifacts/visual glitches with my Voodoo 1 cards on fast PCs, however they all work perfectly in period-correct machines. Personally I never use this card with CPUs faster than a Pentium MMX 166 (it's a very slow card, but it does have that "cool" factor going for it, so it only make sense in period correct builds).

Here's the effect I had when running on a Athlon xp over 500 mhz, not too much different. The big thing there was that I could go into the bios and reduce the multiplier to 5x 100 and then it worked, You can't do that
with Intel P3's. But feel free to keep wasting Your time, and of course I'm fully prepared to eat my words if You are correct.
I guess You did actually try it on a 500mhz chip.

I also never got my V1 cards to work on a 1.4GHz PIII, but a Pentium MMX with much overclocked PCI was just fine. I got a similar checkerboard pattern to appear on the too fast hardware and at first I thought the cards I got are faulty but then I learned they're supposed to be speed sensitive.

I have not tried to determine at what point the card stops working and what will it take to make it work though...

I've used Orchid Righteous 3D on a P3 1400 @ 1050 (100MHz FSB) without trouble across a few games. That's what I used in some old Youtube videos of it. But there's not much point in going beyond about a PII 400. Ye olde P55C is going to hold it back in some games however.

I think it will be all good once he gets the RAM replaced.

I didn't know Voodoo1 could work with an Athlon. The Voodoo2 has some special Athlon drivers that keep it from freezing up.

He is using the Voodoo Graphics for DOS glide compatibility. The latest version of GLIDE2X.OVL for Voodoo Graphics I know that works well in pure DOS was version 2.43, the recent versions shipped with latest drivers only works while running on a Windows 9x operating system and causes the computer to lock up if you try to run it on a pure DOS or in MS-DOS mode.

However the older drivers are CPU speed sensitive and some DOS executables with glide support have the library statically linked.

Gmlb256 wrote on 2021-08-06, 20:40:

He is using the Voodoo Graphics for DOS glide compatibility. The latest version of GLIDE2X.OVL for Voodoo Graphics I know that works well in pure DOS was version 2.43, the recent versions shipped with latest drivers only works while running on a Windows 9x operating system and causes the computer to lock up if you try to run it on a pure DOS or in MS-DOS mode.

However the older drivers are CPU speed sensitive and some DOS executables with glide support have the library statically linked.

Ah I see. I haven't done much with Voodoo1 in DOS in ages. I'm not up on the compatibility issues with Glide versions there.