The Simple & Concise 7900GT Voltmod Tutorial

[inveterate]

Originally posted by: Dexmaus

Originally posted by: inveterate
Yo guys umm,, What did you mean YOUR board was STICKY before you cleaned it.. like it came sticky? or did you make it sticky..?? And by clean you mean the ENTIRE back of the board,, or just certain areas around the place you do the pencil mod

I guess the back of my card came sticky, i just found out that yesterday before cleaning it, its only one side tho, but i decided to clean the whole back board with some acetone and toilet papers, well, right now i've been playing Oblivion for 1 hour, the max temp is 56 with VF900. i'm running at 675/1840 very stable, haven't seen any artifact at all.
not planning anymore overclock, this speed is very good for me right now. thanks everyone here for the help~! great posts

for those people that using the conductive pen from Radioshack, it will be so hard to do it with the pen cause the pointer is too thick, i did this with a sharp pin, i squeeze some silver ink out from the conductive pen on a peice of paper and dip the pin then draw it on the board, it takes some patient, i've re-done it for a couple of times before making it neat.

Sticky,, as in,, EWWW stick,,, tacky sticky,, glue sticky,, or slimy.. how much stick are we talking?

 

[TheRyuu]

Just found out some new info when I did the vgpu and vmem mod.

First off, I have SLI, and I have 2 cards so it basically took me twice as long. (just thought I'd share that)

Second, I did BOTH mod's with BOTH video cards in my case. (yes, it was THAT easy) and thats with a Audigy between both video cards and water cooling, so I wouldn't really try that at home (or anywere). I was sick of tearing apart my system to do things so I got fed up with taking out my WC system just to put on some stupid vmod. So I did it in the case (with the computer off, power off, power unplugged, and video card power (6-pin) unplugged.

From my experince doing the mod I found it extreamly easy to do the vgpu mod and extreamly hard to do the vmem mod. I just couldn't get the memory vmod right. Eventually I got the resistor to ~550 ohms and that got me 2.17v. WTF. All that for .03 below what I wanted. (and the other card was at 2.08v, WTF!!!!!). So I got fed up with that too and did the vmem mod with the computer ON and shaded the resistor, then took a voltage measurement and ajusted accordingly. Not the safest way to do things, but it worked and now both are at 2.21v (idle).

for doing the mods
:| for the vmem
:| for almost frying my computer
for great OC's

Dual 7900GT in SLI @ 670/1800 (1.4v/2.2v)
3dmark05: 15,034
3dmark06: 9495

 

[Keysplayr]

Originally posted by: wizboy11
Just found out some new info when I did the vgpu and vmem mod.

First off, I have SLI, and I have 2 cards so it basically took me twice as long. (just thought I'd share that)

Second, I did BOTH mod's with BOTH video cards in my case. (yes, it was THAT easy) and thats with a Audigy between both video cards and water cooling, so I wouldn't really try that at home (or anywere). I was sick of tearing apart my system to do things so I got fed up with taking out my WC system just to put on some stupid vmod. So I did it in the case (with the computer off, power off, power unplugged, and video card power (6-pin) unplugged.

From my experince doing the mod I found it extreamly easy to do the vgpu mod and extreamly hard to do the vmem mod. I just couldn't get the memory vmod right. Eventually I got the resistor to ~550 ohms and that got me 2.17v. WTF. All that for .03 below what I wanted. (and the other card was at 2.08v, WTF!!!!!). So I got fed up with that too and did the vmem mod with the computer ON and shaded the resistor, then took a voltage measurement and ajusted accordingly. Not the safest way to do things, but it worked and now both are at 2.21v (idle).

for doing the mods
:| for the vmem
:| for almost frying my computer
for great OC's

Dual 7900GT in SLI @ 670/1800 (1.4v/2.2v)
3dmark05: 15,034
3dmark06: 9495

Ummm.... DAYUUUM!!!

 

[TheRyuu]

Originally posted by: keysplayr2003

Ummm.... DAYUUUM!!!

For what ?
The 3dmark scores, the OC, for almost frying my computer, or all of the above

I could probably push the ram to ~1900mhz using a third party app. (coolbits only goes up to 1800mhz) and the vgpu seems stable at that speed (which is a good OC) so why change it. The only way I could really hope to get it higher at a stable speed is to go 1.5v.

 

[Keysplayr]

Originally posted by: wizboy11

Originally posted by: keysplayr2003

Ummm.... DAYUUUM!!!

For what ?
The 3dmark scores, the OC, for almost frying my computer, or all of the above

I could probably push the ram to ~1900mhz using a third party app. (coolbits only goes up to 1800mhz) and the vgpu seems stable at that speed (which is a good OC) so why change it. The only way I could really hope to get it higher at a stable speed is to go 1.5v.

Pretty much all of the above. Nice job! Turned out real nice. You got well beyond 7900GTX speeds for a fraction of the cost. SLI to boot. :beer:

 

[Muhadib]

Volt:
GPU1.5 Conductive ink
MEM2.24 Graphite

Speed
GPU 640 MHz
MEM 1940 MHz

Runs artifact free under ATI tool for 10min, no flashing when running games or ALT+TABing out of 3d games/apps.

These are "safe" numbers, I haven't pushed it to the limit yet.

 

[Keysplayr]

Originally posted by: Muhadib
Volt:
GPU1.5 Conductive ink
MEM2.24 Graphite

Speed
GPU 640 MHz
MEM 1940 MHz

Runs artifact free under ATI tool for 10min, no flashing when running games or ALT+TABing out of 3d games/apps.

These are "safe" numbers, I haven't pushed it to the limit yet.

What are you using to cool the GPU and the memory Muhadib? Got any pics?

 

[Muhadib]

No pix but as you can see in my sig, Im useing AS5 compound with a VF700. 1/2 of my memory modules have sinks on them but im not that worryed about em since the VF700 actively cools the whole side of the card anyhow.

 

[1Dark1Sharigan1]

Well my VF1 Plus finally arrived. Preliminary results are pretty good. About 6-7C cooler than my NV Silencer 5 (fan speed 100%) at load and about 3C cooler at idle. And this is before the AS5 has a chance to settle. It was a pain to install (took me three tries lol) but the end result was pretty impressive. Now my load temps in RTHDRIBL never go above 54C . . . before it would peak around 60-61C . . . this is with my GPU @ 1.4v and 700 Mhz core with no RAM sinks attached. I would imagine adding some RAM sinks would lower the temps even more.

 

[TheRyuu]

My previous overclock of 670/1800 wasn't super stable. Apparently ATI Tool keep giving my artifacts when there were NONE in any of my games (though I didn't play Quake 4/Doom 3 yet which seem to react to overclocking a lot).

Anyway, with Powerstrip I was able to get 658/1880 out of the card. I'm sure with a little more voltage on the ram I could reach 1900 but it doesn't seem worth it right now.

 

[imported_ST]

Originally posted by: wizboy11
Just found out some new info when I did the vgpu and vmem mod.

First off, I have SLI, and I have 2 cards so it basically took me twice as long. (just thought I'd share that)

Second, I did BOTH mod's with BOTH video cards in my case. (yes, it was THAT easy) and thats with a Audigy between both video cards and water cooling, so I wouldn't really try that at home (or anywere). I was sick of tearing apart my system to do things so I got fed up with taking out my WC system just to put on some stupid vmod. So I did it in the case (with the computer off, power off, power unplugged, and video card power (6-pin) unplugged.

From my experince doing the mod I found it extreamly easy to do the vgpu mod and extreamly hard to do the vmem mod. I just couldn't get the memory vmod right. Eventually I got the resistor to ~550 ohms and that got me 2.17v. WTF. All that for .03 below what I wanted. (and the other card was at 2.08v, WTF!!!!!). So I got fed up with that too and did the vmem mod with the computer ON and shaded the resistor, then took a voltage measurement and ajusted accordingly. Not the safest way to do things, but it worked and now both are at 2.21v (idle).

for doing the mods
:| for the vmem
:| for almost frying my computer
for great OC's

Dual 7900GT in SLI @ 670/1800 (1.4v/2.2v)
3dmark05: 15,034
3dmark06: 9495

congrats!

 

[inveterate]

what is the diff between Artifact and Blanking,, is blanking like the Black dots that'll come up?

 

[TheRyuu]

Originally posted by: inveterate
what is the diff between Artifact and Blanking,, is blanking like the Black dots that'll come up?

Artifacting is those little white dots that appear in 3d games (also it can be texture tearing becuase of a memory OC), the blanking seems to just occur on the desktop when running something like ATI tool the screen will go blank for a little bit then come back and then go blank again and then come back in a never ending cycle untill you reboot or your nv disply driver crashes.

 

[Muhadib]

Originally posted by: Muhadib
Volt:
GPU1.5 Conductive ink
MEM2.24 Graphite

Speed
GPU 640 MHz
MEM 1940 MHz

Runs artifact free under ATI tool for 10min, no flashing when running games or ALT+TABing out of 3d games/apps.

These are "safe" numbers, I haven't pushed it to the limit yet.

Looks like 655 / 1960 is my max 100% artifact free O/C. Not one artifact in 2 hours of Atitool testing. RTHDRIBL ran without error as well. 5+ hours of error free game play.

 

[nib95]

Ok, my Silverstone ST75ZF and two Zalman VF900's finally came through today!
The Silverstone PSU is a beast. Amazing quality, truly unbelievable with a great compact fit, durable and quality production, great efficiency and power and it's the same size as my Enermax liberty 500w!! w00t! You can see there's a tonne of heatsinks inside, so I'm sure it'll perform well.

Now all I need is nail varnish remover or the likes and after I clean my boards I'm ready to go!

 

[TitaniumJohnson]

I'll be working up this mod on my dual eVGA 7900 GTs as soon as I can sneak a pair of Zalman VF900's past the wife.

 

[TheRyuu]

I don't understand how people can get their ram so fast. The most I can get out of it (and I'm not even sure if it's stable) is 1880. Maby it's because I have SLI?

 

[inveterate]

yo guys,, ummm. this might be a dumb question, but what kinda pencil you all used.. Just number 2? Dixon Ticonderoga? LOL

 

[1Dark1Sharigan1]

Originally posted by: inveterate
yo guys,, ummm. this might be a dumb question, but what kinda pencil you all used.. Just number 2? Dixon Ticonderoga? LOL

As long as it's graphite.

 

[dman918]

I wish I could get 1800 out of my memory. With cooling, it seems 1700 is the best I get in ATI tool without artifacting there. Maybe I should do the memory mod, but especially with heatsinks on the memory, I should be able to get 1800+, but I don't. Maybe it has something to do with having a standard 7900GT and not a CO or Superclock...

 

[crazylegs]

Have now volt modded the GPU CORE to 1.4v and am running @ 665/ 784(1568) these setting were produced by the CoolBits auto detect device!

Now i need to tweak/ bench/ improve my OC...

QUESTION:

Are there any good guides for OCing/ tweaking/ benching this GPU with reference to 'sweetspots' or levels where the RAM bandwidth needs to be increased to keep up with the CORE?!?

ATM my card is being kept soo nice n cool by the vf900 i'm tempted to jump to 1.5v... but think i want to consolodate and gather some info at this level first!

thanks all

 

[TheRyuu]

Originally posted by: crazylegs
Have now volt modded the GPU CORE to 1.4v and am running @ 665/ 784(1568) these setting were produced by the CoolBits auto detect device!

Now i need to tweak/ bench/ improve my OC...

QUESTION:

Are there any good guides for OCing/ tweaking/ benching this GPU with reference to 'sweetspots' or levels where the RAM bandwidth needs to be increased to keep up with the CORE?!?

ATM my card is being kept soo nice n cool by the vf900 i'm tempted to jump to 1.5v... but think i want to consolodate and gather some info at this level first!

thanks all

See if you can push the core a little further with 1.4v first. Don't worry about the memory until you have the core done right. Right now I'm running at 670mhz on the core stable (although ATI tools doesnt' seem to think so :|). Completly stable in games, 3dmark, rthdribl but not ATI Tool!?!?!??!?!?!??!? WTF? (for me)

Anyway, push core as far as possible with 1.4v, then see if the gains of 1.5v are worth it. Because your already pushing the voltage regulators on the 7900GT as it is. But if you don't fear anything go for it.

And if you do the vmem mod, use a multimeter and don't just go by the resistence (ohms). Power up, go into mobo bios (so that your computer is on and not in windows) and then measure voltage. If it isn't were you want it to be (2.2v) then while the computer is on, make a slight adjustment (add a little more lead), then measure again (be warned, it's dangerous). Anything in the area of 2.2v is fine (2.21, 2.22, 2.23, etc. probably up to 2.25 are safe).

 

[1Dark1Sharigan1]

Yeah ATI Tool is a b.tch . . . I was completely stable in everything with 700 core but ATI Tool would artifact like crazy . . .

 

[weedmeister]

eh...hello... newbie on the forum at your service...

just was wondering how good the "upgraded" stock cooling of this EVGA 7900GT KO would perform under all this OC'ing...

http://www.newegg.com/Product/Product.asp?item=N82E16814130015


would any of you guys know...?

and if I'm not mistaken, this seems to be the exact same fan they are using on their 7900GT Signature Series:

http://www.newegg.com/Product/Product.asp?item=N82E16814130018


seems to be the same card except for 100Mhz difference each on the core and memory and a $111 gap...


edit: another question, if i may, on the subjuct of cleaning the card with acetone... would this also benefit my mobo?

thanks

 

[crazylegs]

Originally posted by: wizboy11

Originally posted by: crazylegs
Have now volt modded the GPU CORE to 1.4v and am running @ 665/ 784(1568) these setting were produced by the CoolBits auto detect device!

Now i need to tweak/ bench/ improve my OC...

QUESTION:

Are there any good guides for OCing/ tweaking/ benching this GPU with reference to 'sweetspots' or levels where the RAM bandwidth needs to be increased to keep up with the CORE?!?

ATM my card is being kept soo nice n cool by the vf900 i'm tempted to jump to 1.5v... but think i want to consolodate and gather some info at this level first!

thanks all

See if you can push the core a little further with 1.4v first. Don't worry about the memory until you have the core done right. Right now I'm running at 670mhz on the core stable (although ATI tools doesnt' seem to think so :|). Completly stable in games, 3dmark, rthdribl but not ATI Tool!?!?!??!?!?!??!? WTF? (for me)

Anyway, push core as far as possible with 1.4v, then see if the gains of 1.5v are worth it. Because your already pushing the voltage regulators on the 7900GT as it is. But if you don't fear anything go for it.

And if you do the vmem mod, use a multimeter and don't just go by the resistence (ohms). Power up, go into mobo bios (so that your computer is on and not in windows) and then measure voltage. If it isn't were you want it to be (2.2v) then while the computer is on, make a slight adjustment (add a little more lead), then measure again (be warned, it's dangerous). Anything in the area of 2.2v is fine (2.21, 2.22, 2.23, etc. probably up to 2.25 are safe).

Thanks for the advice Wizboy... i pushed it up a little bit more - not much just to 671 and ATITool got some of these yellow 'DELTAs' in its artifact test

- these the same as you get when it is still fine in games for you?

- think i might stick @ 650 for a while, after all a 45% increase from stock speeds isnt too bad for a days work