You can buy small square copper heatsinks for pennies that come with thermal tape on them that you can then stick to the regulator and ram chips, with the fan blowing on the card itll cool that regulator down pretty good.

I bought two dozen of them a year or so ago from China for about 5 bucks, pretty much perfect for small ICs. (Yes they are actually copper and not adonized Ally)

Replacing the linear regulator with a PWM regulator completely solves this problem. Similar to how it is done on all Voodoo4. I made myself one of these and am completely happy.

Postman5 wrote on 2025-06-07, 06:42:

Replacing the linear regulator with a PWM regulator completely solves this problem. Similar to how it is done on all Voodoo4. I made myself one of these and am completely happy.

If you are concerned about heat / getting rid of it. This is the only right answer imho.

If you want to keep the card mostly as is: Small heatsinks + moderate airflow over it.

After I made such a heatsink and it didn't help much, I started thinking about a PWM regulator

Yeah, I was thinking maybe a buck converter that could be screwed to the top corner of the card and soldered in place of the linear regulator. Trying to cool it seems like a lost cause. Does the V3 PCI use all 4.6A from the EZ1585CT? Looking at a couple right now that are rated for 5A, but I'm not sure if I need to even go that far. Some general calculations tell me it would be 3-4 amps.

Postman5 wrote on 2025-06-07, 06:42:

Replacing the linear regulator with a PWM regulator completely solves this problem. Similar to how it is done on all Voodoo4. I made myself one of these and am completely happy.

I saw your post on an older thread swapping the EZ1585 with APW7120+2SK3918. After doing some research (and using my brain a bit) I've decided the card is too valuable to be risking some cheap switching voltage regulator.. Probably going to use a third party to print out the PCB with the Sprint file you posted before, but do you recall what parts you used exactly? Thanks!

altarofmelektaus wrote on 2025-06-07, 20:37:

Postman5 wrote on 2025-06-07, 06:42:

Replacing the linear regulator with a PWM regulator completely solves this problem. Similar to how it is done on all Voodoo4. I made myself one of these and am completely happy.

I saw your post on an older thread swapping the EZ1585 with APW7120+2SK3918. After doing some research (and using my brain a bit) I've decided the card is too valuable to be risking some cheap switching voltage regulator.. Probably going to use a third party to print out the PCB with the Sprint file you posted before, but do you recall what parts you used exactly? Thanks!

The file itself indicates the value of each part.

Postman5 wrote on 2025-06-07, 06:42:

Replacing the linear regulator with a PWM regulator completely solves this problem. Similar to how it is done on all Voodoo4. I made myself one of these and am completely happy.

I took the linear VRM off my V3 2000 PCI and tried just feeding it from a wire spliced directly to the 3.3V line of the ATX PSU. I was expecting some voltage ripple to cause artifacts or instability, but it's been working perfectly like this for the past two years. With a 40mm fan on the main heatsink, it runs nice and cool in my compact Mini-ITX build.

sfryers wrote on 2025-06-09, 06:56:

Postman5 wrote on 2025-06-07, 06:42:

Replacing the linear regulator with a PWM regulator completely solves this problem. Similar to how it is done on all Voodoo4. I made myself one of these and am completely happy.

I took the linear VRM off my V3 2000 PCI and tried just feeding it from a wire spliced directly to the 3.3V line of the ATX PSU. I was expecting some voltage ripple to cause artifacts or instability, but it's been working perfectly like this for the past two years. With a 40mm fan on the main heatsink, it runs nice and cool in my compact Mini-ITX build.

This is probably the easiest way. The same is done in all Voodoo3 AGP cards.

I was wondering why I couldn't just do that, but I also heard that it's not the best idea. Not sure why, when like Postman said that's exactly how the AGP variants did it. I ended up going the PWM route to be safe.

altarofmelektaus wrote on 2025-06-07, 17:10:

Yeah, I was thinking maybe a buck converter that could be screwed to the top corner of the card and soldered in place of the linear regulator. Trying to cool it seems like a lost cause. Does the V3 PCI use all 4.6A from the EZ1585CT? Looking at a couple right now that are rated for 5A, but I'm not sure if I need to even go that far. Some general calculations tell me it would be 3-4 amps.

Got Voodoo 3 PCI a while ago and 3.3V linear regulator has been cooking as PCB has turned brown around it etc. So was thinking about DC-DC step down module, but most cheap modules are either underpowered or voltage drop / minimum input voltage is too high / specs are sketchy / there are not enough protection features. So only suitable converter I found would be Pololu D36V50F3; small size, 6.5A, 4.5V minimum input voltage (also at max current on 3V3 module), output over-/undervoltage protection and apparently company behind it is US based so no sketchy Aliexpress crap?

It comes with hefty price though, I could go DIY but TBH i have no energy for it, too much DIY backlog already. What others think, would this Pololu module be good choice?

I would feel better trying it out on a less-desired PCI card first, but if yours is already getting the brown discoloration, I'd say go for it. I went the DIY route and I'm getting amazing results (originally 75C after 1 minute cold boot, now down to 35C!) I have my doubts as to whether ripple would be that much of a problem, but considering this card was pretty much new in condition, I didn't want to risk anything.

jarp wrote on 2025-06-13, 18:11:

altarofmelektaus wrote on 2025-06-07, 17:10:

Yeah, I was thinking maybe a buck converter that could be screwed to the top corner of the card and soldered in place of the linear regulator. Trying to cool it seems like a lost cause. Does the V3 PCI use all 4.6A from the EZ1585CT? Looking at a couple right now that are rated for 5A, but I'm not sure if I need to even go that far. Some general calculations tell me it would be 3-4 amps.

Got Voodoo 3 PCI a while ago and 3.3V linear regulator has been cooking as PCB has turned brown around it etc. So was thinking about DC-DC step down module, but most cheap modules are either underpowered or voltage drop / minimum input voltage is too high / specs are sketchy / there are not enough protection features. So only suitable converter I found would be Pololu D36V50F3; small size, 6.5A, 4.5V minimum input voltage (also at max current on 3V3 module), output over-/undervoltage protection and apparently company behind it is US based so no sketchy Aliexpress crap?

It comes with hefty price though, I could go DIY but TBH i have no energy for it, too much DIY backlog already. What others think, would this Pololu module be good choice?

I have used some of the Pululu modules in the past for other projects. They are well made and quite reliable.
The buck converter IC is a SIC471, which is quite the nice and competent chip. I'm using a SIC454 (big brother) in another project.

I think you're doing nothing wrong with that one in terms of capabilities, though the price is on the high side, as you mentioned.

Cheers

https://www.printables.com/model/762463-3dfx- … ctua-fan-mount/

best way to cool a voodoo3 is right here

maxtherabbit wrote on Yesterday, 12:54:

https://www.printables.com/model/762463-3dfx- … ctua-fan-mount/

best way to cool a voodoo3 is right here

For AGP cards yeah that's good, but we're talking PCI here. The PCI variant uses a step-down voltage regulator that produces a lot of heat. The AGP variants don't have this. A simple fan blowing over it isn't enough, IMO.

I have this exact thing on my PCI V3 3000. I am not concerned by the regulator whatsoever and the card runs great