[aaronjb]

Overvolted my eVGA 7900 GT Superclocked cards to 1.55 volts. Used this 1.55 mod (found on the extremesystems.org 7900 forum), completed with a conductive pen purchased at Radio Shack:



And here's the first 3dmark06 run @ 630/850(1700):



http://service.futuremark.com/compare?3dm06=229070

Currently 18th on the 3Dmark 7900 GT / Any Driver list. Just installed a Silverstone 120mm blowing at the vid cards; let's see how high I can get these puppies to go.

Other specs:

Athlon X2 4200 @ 2.5 Ghz
2 GB RAM

Modded resorator cooling the GPUs, 42 is the highest GPU load temp so far.

[Alchemy1]

I thought you had to remove a resistor or two to disable the overvolt protection bulit into the card for anything over 1.4 volts? Is that your max core clock? I have seen tons of people around 700 w/ only the 1.4 v-mod.

[aaronjb]

Originally Posted by Alchemy1

I thought you had to remove a resistor or two to disable the overvolt protection bulit into the card for anything over 1.4 volts? Is that your max core clock? I have seen tons of people around 700 w/ only the 1.4 v-mod.

I used a multimeter to check the voltage, and it's 1.55 on both cards. I spent a lot of time on the ES forums today, reading the various mod techniques. 1.55 is the highest that can be acheived without removing/replacing resistors.


I'm just starting to crank these things up. Just had a 3DMark06 run at 690 / 1800, but I'm seeing lower overall scores. Not sure what to attribute that to.

So, hrm. Got all excited, then lower scores.

But Oblivion runs like a champ.

[aaronjb]

Just noticed on the 3DMark ORB that my initial score is the fastest 7900 score among 2450 - 2550 Ghz processors (all types). Guess I should just be happy with that.

Among all GPUs from 2450 - 2550, that score is 7th.

[Alchemy1]

Originally Posted by aaronjb

I used a multimeter to check the voltage, and it's 1.55 on both cards. I spent a lot of time on the ES forums today, reading the various mod techniques. 1.55 is the highest that can be acheived without removing/replacing resistors.

NICE, you learn something new everyday. 1.55v without any detailed (removing /replacing things) modding is good enough for me. I have got to get my hands on one of these cards, but I refuse to pay over MSRP(well, $20+ more)...I will wait.

[aaronjb]

Ran a few more benches last night. The highest stable, non-artifacting core speed I'm reaching is 735, and the hightest (non-overvolted) vMem speed I'm hitting is 890. However, it's not translating into higher 3DMark06 runs, so I'm probably CPU bound.

Tonight I'll try and push the CPU higher (2.7?) and run some more benchmarks. However, I'm pleased with my results, and just as happy with the 7900s. Whether or not they're binned, I don't know, but reaching GTX speeds on a GT board seems to indicate that the cores are identical.

[snakeskinner]

Originally Posted by aaronjb

Ran a few more benches last night. The highest stable, non-artifacting core speed I'm reaching is 735, and the hightest (non-overvolted) vMem speed I'm hitting is 890. However, it's not translating into higher 3DMark06 runs, so I'm probably CPU bound.

Tonight I'll try and push the CPU higher (2.7?) and run some more benchmarks. However, I'm pleased with my results, and just as happy with the 7900s. Whether or not they're binned, I don't know, but reaching GTX speeds on a GT board seems to indicate that the cores are identical.

You might want to do the mod to change the switching frequenzy. Either do the pencil trick, or solder a 100K resister in parallel. That seems to help some people, others it doesn't. But its worth a try.

My card is at 1.5v and I can run 724/900. I've been playing around with 3dmark05, and i've only run 06 once. But I got 6750 with a single card, and I would think your scores should be a little higher than they are. I think I should be able to get 7000 in 06 before I mod up to 1.55v. I think something is holding you back. It could be the cpu, but it might be that resistor on the card too.

Also, powerstrip might not be setting all your clocks right. I had a problem with ati tool doing that, sometimes it would show the right clocks, but my score would be like 3000 points lower than normal in 3dmark05, so I know something wasn't right. Since I fixed coolbits where I can use it now, I haven't had that problem anymore and my scores have went up.

http://service.futuremark.com/compare?3dm06=229525

Marlon

[VinnyTAMU]

Dang, that is a crazy 3DMark06 score.

[aaronjb]

Originally Posted by snakeskinner

Also, powerstrip might not be setting all your clocks right. I had a problem with ati tool doing that, sometimes it would show the right clocks, but my score would be like 3000 points lower than normal in 3dmark05, so I know something wasn't right. Since I fixed coolbits where I can use it now, I haven't had that problem anymore and my scores have went up.

I have a feeling that the problem might be related to PowerStrip. I normally overclock with RivaTuner, but there's no 79xx support yet (AFAIK). I tried upping the clocks with the stock nVidia control panel, but the highest that I could set and "test" on was 730 / 900. Even PowerStrip wouldn't let me exceed 735 on the GPU.

Also, I'm going to see what kind of watts are being pulled under full load. Not sure, but I think I may have a power supply issue.

I'm using the default 3DMark06 application profile. Should I edit this, or change some individual settings?

[snakeskinner]

Originally Posted by aaronjb

I have a feeling that the problem might be related to PowerStrip. I normally overclock with RivaTuner, but there's no 79xx support yet (AFAIK). I tried upping the clocks with the stock nVidia control panel, but the highest that I could set and "test" on was 730 / 900. Even PowerStrip wouldn't let me exceed 735 on the GPU.

Also, I'm going to see what kind of watts are being pulled under full load. Not sure, but I think I may have a power supply issue.

I'm using the default 3DMark06 application profile. Should I edit this, or change some individual settings?

You can modify coolbits to allow you to overclock higher if you run out of range. If I want to go higher than what coolbits will let me test at, I set the clock in ati tool, and then go back to the nvidia control panel, and it will usually let me set it there then so it will set that way at startup. This works sometimes, and sometimes it doesn't.

I would close powerstrip down completly, and run a benchmark with as high of clocks at coolbits will let you and see what the score is. Then use powerstrip to set the same clocks and run the same benchmark again. If there is a difference, you know powerstrip is causing a problem. If not, you might look to the power supply.


Marlon

[spydeymon]

[QUOTE=aaronjb]Overvolted my eVGA 7900 GT Superclocked cards to 1.55 volts. Used this 1.55 mod (found on the extremesystems.org 7900 forum), completed with a conductive pen purchased at Radio Shack:

QUOTE]


Hey arron would you mind showing me how to get only 1.5v i dont want to give it 1.55v cause i only have a zalman 700-cu and at 1.4v load temps hit 49
so i was just curious what 1.5v would do and that pic you have is for 1.55v
thanks

[snakeskinner]

[QUOTE=spydeymon]

Originally Posted by aaronjb

Overvolted my eVGA 7900 GT Superclocked cards to 1.55 volts. Used this 1.55 mod (found on the extremesystems.org 7900 forum), completed with a conductive pen purchased at Radio Shack:

QUOTE]


Hey arron would you mind showing me how to get only 1.5v i dont want to give it 1.55v cause i only have a zalman 700-cu and at 1.4v load temps hit 49
so i was just curious what 1.5v would do and that pic you have is for 1.55v
thanks

To get 1.5v, you need to connect the 2 solder pads next to each other on D508 and D511 to any ground on the card. That would be the right solder pad on D508, and the left solder pad on D511. I put a tiny blob of solder to connect those 2 solder pads to each other, and then soldered a thin wire from there to groud, thus connecting BOTH points to ground, giving 1.5 volts. If you don't feel comfortable soldering this, you can use conductive ink or paint. Just make sure to connect both points, they are right next to each other, and then paint a line to ground and your done, 1.5 volts accomplished.


Marlon

[spydeymon]

would you mind showing me a pic cause i didnt really get it

[snakeskinner]

Originally Posted by spydeymon

would you mind showing me a pic cause i didnt really get it

Here is the best pic I can find. Its for 1.55v, so don't do the short line that connects the bottom solder pad to ground. If you just do D508 and D511 to groud, you will have 1.5v. Follow this guide here, its very simple to do.
http://www.xtremesystems.org/forums/...ad.php?t=94177

Marlon

[spydeymon]

thanks i went ahead and just did the 1.55v mod but it didnt help the oc when i did auto detect with coolbits and whenever i try the vmem mod to get 2.2v with the pencil ive tried 4 dif pencils and they always depreciate the oc mem would only go to 720 otherwise it always stops at 784 with auto detect