7900GT Volt mod ( not by bios) - GT @ 800MHZ!!!

[skankinred]

All you need is conductive paint. Copper or silver, make sure it's 100%. I reccomend CircuitWriter http://store.caig.com/s.nl/sc.2/category.174/.f
First remove the resistor marked above and replace it with a 50K ohms resistor. This will give you 1.5v for VGPU.

If more voltage is desired, I suggest you move onto step 2: removing the 2 resistors marked to disable overcurrent protection for the card.

You can then move onto step 3: Soldering and connecting this point to any grounded spot. This will give you 1.6v.

Instead of step3, you can do step 4 if 1.7v is required.

Found on:
http://www.xtremesystems.org/forums/showpost.php?p=1357986&postcount=188



Many have done it at xtreme:
http://www.xtremesystems.org/forums/showthread.php?t=92874&page=8

User Powerstrip to OC:
http://www.entechtaiwan.com/util/ps.shtm

Nvidia 7900GT compared to other graphics cards:
http://sg.vr-zone.com/?i=3335

Details @ VR Zone: http://www.vr-zone.com/print.php?i=3437
Power Consumption/Heat Output/Chart
Geforce 7900GT @ Default voltage/Speed 64 watts
Geforce 7900GT @ 745MHz 1.5v 87 watts
Geforce 7900GT @ 780MHz 1.6v 101 watts
Geforce 7900GT @ 800MHz 1.7v 111 watts

 

[OraneBana]

Man, found something similar here at http://www.vr-zone.com/?i=3437&s=3

They got 800core on air. Check it out. Hope the link's working. Otherwise just pop in at www.vr-zone.com ......should be in the main page for now. Its the latest article.

 

[FITCamaro]

Are they saying they got that memory up to 2126 DDR? Holy crap. Imagine if they release a 512MB version of the 7900GT. Be owning 7900GTXs for 2/3 the price. Course I don't know if I'm willing to take off and replace resistors on the back of my graphics card.

 

[Syzler]

Are they saying they got that memory up to 2126 DDR? Holy crap. Imagine if they release a 512MB version of the 7900GT. Be owning 7900GTXs for 2/3 the price. Course I don't know if I'm willing to take off and replace resistors on the back of my graphics card.

Umm....The GTX is a 512 version of the GT. They are the same core. The only difference is the GTX runs stock at 1.4V and it uses 512 of lower latency GDDR.

 

[skankinred]

This topic is the only source of information you need when looking to buy a Nvidia card. GT@ 800mhz is the same max OC that a GTX can go to. so for $300 you can smoke a GTX / x1900XTX any day. This card will last you for a couple years. You won't find a stock card comparable for awhile now. Even if newer cards come out, they will only be slightly higher clock speeds than the stock GTX which is 650.

 

[mesarectifier]

How fast do you reckon someone could push their 7800GT with water cooling and this mod?

Graphics cards with more power than a PC did 4 years ago, it's totally nuts.

 

[skankinred]

Anything above 1.4V would require water cooling. 1.7V is the highest you can safely go. So 800mhz would be your answer.

 

[mesarectifier]

'The highest you can safely go'

What about unsafely? I was more thinking of the sort of people who do crazy extreme OC; we see CPUs at 6/7ghz quite regularly, is there no way you could push a GPU to say, 1.5ghz?

 

[skankinred]

...

 

[skankinred]

This is extreme overclocking. Soldering resistors and replacing capacitors? c'mon... Any more voltage than 1.7 and the GPU will fry. This is an 80% OC. Try getting that much on a cpu even with Liquid Nitro.

 

[mesarectifier]

As you may have guessed I'm not really an overclocker/ist (??)

I just thought that seeing as people can get such huge frequencies out of CPUs perhaps the same is possible for GPUs. Is the architecture so different? Is the clock not controlled by a multiplier?

 

[skankinred]

This is a huge OC. The stock is 450mhz. Going to 800mhz is a HUGE jump. Try to OC a Pentium-3 500mhz to 850mhz; won't happen. It's easier to go from 3ghz to 4ghz than 500mhz-850mhz. The ratio is less when the starting clock speed is higher to begin with.

We are lucky the 7900 series is so OC friendly to volt mods. The 7800 didn't benefit from volt mods at all.

 

[p05esto]

that's pretty cool. Any of you actually do this to your $300 card? I know I will be getting this card once NewEgg gets them in stock and maybe a game bundle comes out in a couple months.

I'm pretty handy with a soldering gun but my hands will sweat knowing I'm just once slip away from flushing $300 bones down the toilet.

So, who has done this?

 

[ChipDeath]

I haven't done this, but I did a Voltmod to my 9800Pro. I did kill it, but only through excessive voltage... It was the idiotic application of the mod, rather than the mod itself that was the problem there... :lol:

It's not too bad. I didn't even use a soldering iron with a fine tip (which I'd recommend), but a big fat unwieldy thing, and[/] I'm not that great at soldering - I occasionally make leads and have replaced dead caps on a mobo and gfx card successfully, but don't do it often enough to really develop real 1337 skillz or whatever.

 

[ChipDeath]

.... And if anyone Sees a reliable PCI-E 6800GS Voltmod let me know!...

Oblivion is killing my card.... I reckon life would be sweeter if I could get 650Mhz or more on the core, but I hit artifacts at any more than 520Mhz (in fact I get some very minor ones in a couple of 3dmark tests with 520Mhz, but games are all ok)

I've got a VGA silencer on there, so my cooling is significantly better than stock already, and I don't especially want to switch to water. (Although I might switch to a different air cooler... I do have a stock A64 HSF lying around at home... )

 

[skankinred]

that's pretty cool. Any of you actually do this to your $300 card? I know I will be getting this card once NewEgg gets them in stock and maybe a game bundle comes out in a couple months.

I'm pretty handy with a soldering gun but my hands will sweat knowing I'm just once slip away from flushing $300 bones down the toilet.

So, who has done this?

Did you read my first post? Click on the link to xtremesys to see that YES many people have done this including myself.

.... And if anyone Sees a reliable PCI-E 6800GS Voltmod let me know!...

Check out xtremesys forum section, the same section the link is to, has 6800 mods. You can also do a bios mod to increase voltage since you're cap'd on your core as you're seeing artifacts. Up the voltage and you can up the core more. But be careful, voltage=a lot of heat. Only up it a few .x volts with air.

 

[ChipDeath]

But be careful, voltage=a lot of heat. Only up it a few .x volts with air

Hey, I own the 2V 9800Pro 'Paperweight edition'... I know all about the dangers here :lol:

Whenever I've looked into the BIOS mods, Nibitor doesn't list the PCI-E 6800GS in the list of compatible cards. I'm hesitant to try any other 6800 BIOS due to the fact it is a totally different core to most of the others (smaller process (11nm Vs.. 13?)+ only 12 pipes, not just a higher-up one with bits disabled)

I've seen a few people with 700Mhz on air with them, so hopefully I'll get a nice increase if I do the voltmod...

 

[skankinred]

I never said heat will kill it. I said be careful since he's on air that he can only go up a few .x volts since it will increase the heat tremendously.

 

[ChipDeath]

I'll take a better look next time I get it out of the case, but I'm quite wary about v-mods since it's a smaller process, so is (I guess) running a lower stock voltage than all the other 6800 cores, and therefore will probably have different voltage regulation circuitry.

I think I've seen a couple of hard v-mods here and there, but none of them have been particularly good guides, and I was just waiting a while to see if anyone does it with a BIOS.

I'll be a bit more cautious than I was with the 9800Pro. :lol:

If stock V's 1.3, I'll not go higher than around 1.45 or so... I reckon the silencer should cope.

I'm also going to loosen the silencer's backing plate, and stick one of my Antec's Temp sensors in so it's right on the PCB directly behind the core (then tighten the thing up, obviously) should give a fairly accurate and easy temp. check.

But I'm busy buying a house and hopefully moving into it in a couple of days, so I'm far too busy at the moment... /