VOGONS


Voodoo 3 Undervolting/Undercloocking

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First post, by Jackal1983

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Any options for this? I have a freed up PCI Voodoo 3 (was gonna use it in a C3 Nehemiah/ 440BX based build that doesn't have AGP ports) and I figure I'll use it in my MediaGX build. It obviously can't take advantage of its full power and we all know it tends to run hot (already put good thermal past in between the main mosfet and the heatsink and between the heatsink and the board) so I'd like to bump down the voltage and clocks to , say, voodoo 3 1000 levels. Any way of doing that short of flashing the vbios. I know it can be underclocked in the unlocked driver settings, but does that back the voltages down, too?

Reply 1 of 26, by Doornkaat

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To the best of my knowledge the Avenger cards use LDOs with their output voltages determined by resistor configurations on the PCB. There is no way to control the voltages through software.
The transistor with the heatsink on PCI V3s is used to generate +3.3V afaik because back then you couldn't rely on the PCI slots to supply that voltage.
Lowering the clocks will lower the total power draw a bit though but a bit of airflow over the cards is still the best solution imho.

Reply 2 of 26, by Joseph_Joestar

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If heat is the primary concern, install a PCI fan bracket below the Voodoo3. With two 80 mm fans, you should have no problems.

As for downclocking, I think this might be possible through the 3DFX Control Panel, but that would only work under Windows of course.

PC#1: Pentium MMX 166 / Soyo SY-5BT / S3 Trio64V+ / Voodoo1 / OPTi 82C930 / AWE64 Gold / SC-155
PC#2: AthlonXP 1700+ / Abit KT7A / Voodoo3 / Audigy1 / Vortex2
PC#3: Athlon64 3400+ / Asus K8V-MX / 5900XT / Audigy1
PC#4: i5-3550P / MSI Z77A-G43 / GTX 650Ti / X-Fi

Reply 3 of 26, by Jackal1983

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Joseph_Joestar wrote on 2022-02-26, 10:28:

If heat is the primary concern, install a PCI fan bracket below the Voodoo3. With two 80 mm fans, you should have no problems.

As for downclocking, I think this might be possible through the 3DFX Control Panel, but that would only work under Windows of course.

Well a fan blowing from the side perpendicular to the card will have to do. The case has 120mm fan mounts there. The other pci slot has a promise ultra ATA card in it. I'll underclock it to V3-1000 speeds and keep dropping speeds till I lose performance.

Reply 4 of 26, by Cuttoon

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Sounds a bit like wasting a perfectly good voodoo and the PCI ones are approaching something of a holy grail nowadays, don't they?

But if you insist, what Doornkaat writes seems plausible and doable for a layman. Meaning, find out how and change said resistor.
Or, since the power consumption of that chip might actually not be that huge, you might even get away with simply bypassing the main conduct with some kind of external load, if Ohm's law means anything to you.
(Ya know, what Germans know about resistance.)
So, that will not reduce the power consumption of the rig, but of the chip.

Software, frequency: I remember a tool called the riva tuner. Was named for the Nvidia card, but did a lot more.
https://www.philscomputerlab.com/riva-tuner.html

Anyway, running hot is not a vice per se. They do work, don't they?

Anecdotal, but I admit, I've actually fried my original '3000, maybe 12 years ago.
Remember, that was the time when an obsolete voodoo was just a piece of junk.
(Which is the reasons why today it's a rare piece of junk.)

It got replaced by a Gf4 around '02 and went on to my father's Athlon - that was an evil scheme of my brother and me to groom it as a standby lan party rig.

We had previoulsy fried the cheap biostar slot 1 motherboard by adding a gf256 to it and I installed the voodoo once I realized the VGA signal of that gf256 looked like a potato.

So, it croaked a few years later.

Back then we didn't know any better and didn't care to much about the hardware longevity of daddy's solitair machine.
But looking at that late 90s mini tower case some years later: That thing was a death trap.
Hardly any ventilation, whatsoever. Shouldn't have housed anything beyond socket7, unmodded.

So, if you've heard about dying Voodoo3s, its probably due to extended stupidity of that kind.

IMHO: Leave the slot below it unpopulated and use a serrated bracket or none, you should be fine.

I like jumpers.

Reply 5 of 26, by Jackal1983

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Cuttoon wrote on 2022-02-27, 04:23:
Sounds a bit like wasting a perfectly good voodoo and the PCI ones are approaching something of a holy grail nowadays, don't the […]
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Sounds a bit like wasting a perfectly good voodoo and the PCI ones are approaching something of a holy grail nowadays, don't they?

But if you insist, what Doornkaat writes seems plausible and doable for a layman. Meaning, find out how and change said resistor.
Or, since the power consumption of that chip might actually not be that huge, you might even get away with simply bypassing the main conduct with some kind of external load, if Ohm's law means anything to you.
(Ya know, what Germans know about resistance.)
So, that will not reduce the power consumption of the rig, but of the chip.

Software, frequency: I remember a tool called the riva tuner. Was named for the Nvidia card, but did a lot more.
https://www.philscomputerlab.com/riva-tuner.html

Anyway, running hot is not a vice per se. They do work, don't they?

Anecdotal, but I admit, I've actually fried my original '3000, maybe 12 years ago.
Remember, that was the time when an obsolete voodoo was just a piece of junk.
(Which is the reasons why today it's a rare piece of junk.)

It got replaced by a Gf4 around '02 and went on to my father's Athlon - that was an evil scheme of my brother and me to groom it as a standby lan party rig.

We had previoulsy fried the cheap biostar slot 1 motherboard by adding a gf256 to it and I installed the voodoo once I realized the VGA signal of that gf256 looked like a potato.

So, it croaked a few years later.

Back then we didn't know any better and didn't care to much about the hardware longevity of daddy's solitair machine.
But looking at that late 90s mini tower case some years later: That thing was a death trap.
Hardly any ventilation, whatsoever. Shouldn't have housed anything beyond socket7, unmodded.

So, if you've heard about dying Voodoo3s, its probably due to extended stupidity of that kind.

IMHO: Leave the slot below it unpopulated and use a serrated bracket or none, you should be fine.

Eh, I'd rather not mod the card because of its value. A 120mm fan blowing directly onto the card should cool that mosfet that runs hot at a minimum (I've heard that thing and the electrolytics next to it are what kill these cards, dumbass decision by 3DFX to not put ANY thermal interface material b/w the HS and mosfet or the HS and the board) and keep the card itself cool, especially with underclocking. I might add a fan to the front of the case , that way I can get arflow across the board from 2 directions. Not as good as blowing directly onto it, of course, but with an underclock it should suffice. I was just hoping the voltage could be dropped in software like the clocks either via BIOS modding or applications. The card itself looks VERY nice, damn near new, some VERY slight color changes on the board behind the mosfet, it'd be a shame not to use it. I might take another crack at installing the DMA drivers for the board (they're REALLY REALLY finnicky), however. If I can get them running somehow, I have a dual fan slot cooler I can go with. As to why I'm using it: I have 2 other PCI GPUs that would work for this board. One is a NOS Riva 128 that I had planned on using (basically perfect from a period approopriatness perspective) but all of a sudden quit putting out video. It's still detected in W98 and the drivers install if I use the board's onboard video, it just will to put anything out. The other is a Vanta I revived with a full recap, a nice enough card but it doesn't have glide (I'd like to play some early 3d games on this rig and its ideal from a power standpoint for playing around with those older APIs). I also have a Rage 2 Turbo AIW that I'll eventually play around with on this rig as well (wanna try Tomb Raider and Mechwarrior 2), I'd just like to start with the Voodoo. If I can ever figure out what's up with the Riva and get the DMA drivers working, I can go with my original plan to use the Riva and a Voodoo 1 I have. And no, I'm not using the onboard video, it's crap in multiple ways. Look up Gona's DOS compatability matrix under "Cyrix Xpress Graphics". The image quality is also garbage.

Reply 6 of 26, by Cuttoon

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Jackal1983 wrote on 2022-02-27, 05:33:

Eh, I'd rather not mod the card because of its value.

I wouldn't have recommended it, but since you asked?

Jackal1983 wrote on 2022-02-27, 05:33:

A 120mm fan blowing directly onto the card should cool that mosfet that runs hot at a minimum

My point exactly, in a half-way well-ventilated case, it should be fine. Back in '99, cases relied on some holes up front, maybe on the side and the PSU fan. Which usually was overpowered and noisy. So, themal regulated PSU fans that only barely serve the PSU's cooling need might also have been what killed the odd component.

Jackal1983 wrote on 2022-02-27, 05:33:

I've heard that thing and the electrolytics next to it are what kill these cards

Interesting, that gives me hope for resurrecting my V3, it's still somewhere in the basement. Replacing caps and regulator sound doable.

Jackal1983 wrote on 2022-02-27, 05:33:

dumbass decision by 3DFX to not put ANY thermal interface material b/w the HS and mosfet or the HS and the board

The STB Voodoos may be 'hecho en Mexico', but actually known for decent build quality. I wouldn't blame them. Thermal grease was rather unknown back then, remember, the Nvidia Riva 128 and Voodoo2 still came without any heat sink at all. Let's face it, consumer cards were not supposed to live forever, even back in '99, especially if it saved a buck.

Active fans on graphics cards back then were noisy as fuck, usually. I actually silenced several obsolete cards for the low-tier use described above. Simply by pulling the fan cable, or one gf2 Ti by replacing the stock cooler with a socket 7 piece, no fan. They probably wouldn't run stable in prolonged 3d duty, but non of them ever died on me.

I have one V3 from the bay for a Euro, the previous owner had somehow applied a fan to it. Yep, shame, that looks like shit.
And a third one in mint condition that an old friend of the non-tinkering confession once gave me when I pointed out that I know the video card in his discarded rig by name. Still didn't occur to me to offer him anything beyond a symbolic beer back then - no one expected them to turn into fetish objects that pull 100 €+ in auctions...

A less "holy" option for a ca. 1997 build might be a s3 virge or savage, iirc. The Riva, obviously. I had a Mystique back then. Expensive but useless 😜

Funny you'd mention the onboard graphics. I happen to have an original "Igel" thin client with a media gx core. Really nifty little thing, but I looked up the onboard graphics on exactly that list - yeah, they're shit.

I like jumpers.

Reply 7 of 26, by Jackal1983

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Cuttoon wrote on 2022-02-27, 06:16:
I wouldn't have recommended it, but since you asked? […]
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Jackal1983 wrote on 2022-02-27, 05:33:

Eh, I'd rather not mod the card because of its value.

I wouldn't have recommended it, but since you asked?

Jackal1983 wrote on 2022-02-27, 05:33:

A 120mm fan blowing directly onto the card should cool that mosfet that runs hot at a minimum

My point exactly, in a half-way well-ventilated case, it should be fine. Back in '99, cases relied on some holes up front, maybe on the side and the PSU fan. Which usually was overpowered and noisy. So, themal regulated PSU fans that only barely serve the PSU's cooling need might also have been what killed the odd component.

Jackal1983 wrote on 2022-02-27, 05:33:

I've heard that thing and the electrolytics next to it are what kill these cards

Interesting, that gives me hope for resurrecting my V3, it's still somewhere in the basement. Replacing caps and regulator sound doable.

Jackal1983 wrote on 2022-02-27, 05:33:

dumbass decision by 3DFX to not put ANY thermal interface material b/w the HS and mosfet or the HS and the board

The STB Voodoos may be 'hecho en Mexico', but actually known for decent build quality. I wouldn't blame them. Thermal grease was rather unknown back then, remember, the Nvidia Riva 128 and Voodoo2 still came without any heat sink at all. Let's face it, consumer cards were not supposed to live forever, even back in '99, especially if it saved a buck.

Active fans on graphics cards back then were noisy as fuck, usually. I actually silenced several obsolete cards for the low-tier use described above. Simply by pulling the fan cable, or one gf2 Ti by replacing the stock cooler with a socket 7 piece, no fan. They probably wouldn't run stable in prolonged 3d duty, but non of them ever died on me.

I have one V3 from the bay for a Euro, the previous owner had somehow applied a fan to it. Yep, shame, that looks like shit.
And a third one in mint condition that an old friend of the non-tinkering confession once gave me when I pointed out that I know the video card in his discarded rig by name. Still didn't occur to me to offer him anything beyond a symbolic beer back then - no one expected them to turn into fetish objects that pull 100 €+ in auctions...

A less "holy" option for a ca. 1997 build might be a s3 virge or savage, iirc. The Riva, obviously. I had a Mystique back then. Expensive but useless 😜

Funny you'd mention the onboard graphics. I happen to have an original "Igel" thin client with a media gx core. Really nifty little thing, but I looked up the onboard graphics on exactly that list - yeah, they're shit.

Yeah, I know the cards are of really good quality. My complaint is more of an engineering one, and that it would have been nicer if they had done a bit more for heat mitigation or gone with solid caps around that mosfet. I'm actually planning on hunting down a Virge DX with 35ns memory (seems to have the right mix of compatabilty and overclockability) to play with on this board, as well as a Rendition Verite ( maybe the softlocked Diamond variant). Those 2 plus the Rage 2 Pro pretty much cover all the early proprietary APIs with a real library, excepting PowerSGL. Between the expense of the cards (hard to find for less than a kings ransom) and PowerVR's reliance on using the CPU for floating point calculations make this one a no no on this rig even if I owned one. Better an Athlon or a P3 for that.

Reply 8 of 26, by The Serpent Rider

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Underclocking alone usually provides very little impact on thermal stress.

I must be some kind of standard: the anonymous gangbanger of the 21st century.

Reply 9 of 26, by mockingbird

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The Serpent Rider wrote on 2022-02-28, 17:49:

Underclocking alone usually provides very little impact on thermal stress.

I beg to differ... I modded my Geforce3 Ti500 (240/250) into basically a Ti200 (175/200) and the heat level (based on touch and feel) went down an appreciable amount. Not as much as I wanted, but still enough to keep those clocks permanent (bios mod).

There's not much room with a Voodoo OTOH since the card pretty much needs everything it can get...

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Reply 10 of 26, by The Serpent Rider

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I modded my Geforce3 Ti500 (240/250) into basically a Ti200 (175/200)

Unlike undervolting, underclocking has linear scale. So for 50% TDP reduction, you also need to reduce chip clock by half, but realistically - by more than a half. Not an optimal solution, because it will drastically reduce performance.

I must be some kind of standard: the anonymous gangbanger of the 21st century.

Reply 11 of 26, by mockingbird

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The Serpent Rider wrote on 2022-02-28, 19:46:

I modded my Geforce3 Ti500 (240/250) into basically a Ti200 (175/200)

Unlike undervolting, underclocking has linear scale. So for 50% TDP reduction, you also need to reduce chip clock by half, but realistically - by more than a half. Not an optimal solution, because it will drastically reduce performance.

Granted... But let's not underestimate endurance ratings on ICs, or more to the point, the exponential gain in IC longevity with even a suboptimal or moderate reduction in heat. Voodoo3 SDRAM models (or SGRAM for that matter) push RAM to 175Mhz or 143 Mhz depending on the model (3000 vs 2000)... 175Mhz with SDRAM was far above anything I remember for that area, and who knows if even 143Mhz was attainable by PC133 chips back in the day.

So is it that unreasonable to underclock your Voodoo3 3000 with 6ns RAM to the 143Mhz of the 2000?

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Reply 13 of 26, by The Serpent Rider

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So is it that unreasonable to underclock your Voodoo3 3000 with 6ns RAM to the 143Mhz of the 2000?

It's pointless.

I must be some kind of standard: the anonymous gangbanger of the 21st century.

Reply 14 of 26, by mockingbird

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Doornkaat wrote on 2022-02-28, 21:20:

Don't confuse JEDEC specifications for SDRAM DIMMs and the limits of SDR SDRAM chips in 1999.

Don't take my word for it, see for yourself.

He's scoring extreme overclocks on late, close to 2005 era modules... The 3000 and 3500 came clocked at 166Mhz and 183Mhz like you say, in mid-1999.

Yes, I think the silicon was being pushed beyond the capabilities of that time.

The Serpent Rider wrote on 2022-02-28, 21:40:

It's pointless.

No. More speed equals more heat. More heat equals a shorter lifespan.

Good luck to those looking for 2MB 6ns (166Mhz) replacement chips (you need 8 of them, unless you can diagnose which one is it you might need to replace).

7ns chips OTOH are much easier to come by.

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Reply 15 of 26, by Doornkaat

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mockingbird wrote on 2022-03-01, 00:33:
Don't take my word for it, see for yourself. […]
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Doornkaat wrote on 2022-02-28, 21:20:

Don't confuse JEDEC specifications for SDRAM DIMMs and the limits of SDR SDRAM chips in 1999.

Don't take my word for it, see for yourself.

He's scoring extreme overclocks on late, close to 2005 era modules... The 3000 and 3500 came clocked at 166Mhz and 183Mhz like you say, in mid-1999.

Yes, I think the silicon was being pushed beyond the capabilities of that time.

But that's exactly my point: You can not compare 16MB on a graphics card to 128MB+ DIMMs on a mainboard with an overclocked memory controller.

Reply 16 of 26, by vvbee

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With a K6 300 (bottlenecking), I've seen temps reduced by up to 4 C load and idle by downclocking from 143 to 100 MHz, with 0-5% loss in performance up to 800 x 600 (tested in Quake 3, Need for Speed 5, 3DMark 99). So not a big reduction in temps, but also no clear benefit in running the card full blast.

Reply 17 of 26, by NostalgicAslinger

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Here are the Avenger VCores of the Voodoo 3 1000 until 3500, from the 3dfx Voodoo 3 databook:

Voodoo 3 1000: 125 MHz, 2.20V Vcc
Voodoo 3 2000: 143 MHz, 2.55V Vcc
Voodoo 3 3000: 166 MHz, 2.69V Vcc
Voodoo 3 3500 183MHz, 2.76V Vcc

That's the reason ,why a V3 1000 runs stable without any cooling.

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Reply 18 of 26, by Jackal1983

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vvbee wrote on 2022-03-02, 04:30:

With a K6 300 (bottlenecking), I've seen temps reduced by up to 4 C load and idle by downclocking from 143 to 100 MHz, with 0-5% loss in performance up to 800 x 600 (tested in Quake 3, Need for Speed 5, 3DMark 99). So not a big reduction in temps, but also no clear benefit in running the card full blast.

Thanks, that kind of data was what I was curious about. Between that honking huge aluminum heatsink that came attached to the chip and an underclock I should get a decent reduction in temps. Hopefully I'll get a decent temp drop over that mosfet as well.

Reply 19 of 26, by Jackal1983

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NostalgicAslinger wrote on 2022-03-02, 13:18:
Here are the Avenger VCores of the Voodoo 3 1000 until 3500, from the 3dfx Voodoo 3 databook: […]
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Here are the Avenger VCores of the Voodoo 3 1000 until 3500, from the 3dfx Voodoo 3 databook:

Voodoo 3 1000: 125 MHz, 2.20V Vcc
Voodoo 3 2000: 143 MHz, 2.55V Vcc
Voodoo 3 3000: 166 MHz, 2.69V Vcc
Voodoo 3 3500 183MHz, 2.76V Vcc

That's the reason ,why a V3 1000 runs stable without any cooling.

And those Vcores are not controlled by the Vbios? I actually have a AGP 1000 with some really good SDRAM (6ns) that's going into a C3 rig that I was planning on bumping up to roughly V3-2000 speeds (I have a pretty hefty HS attached as well as a fan) but if the Vcore is not set in the bios but via resistor config then it might be more of a longshot.