7900 gt voltmod to 1.4 or 1.5?

[pyro786]

So i have a 7900gt, with a zalman vf700 on it. It idles at 42c, and is oc'd to 564/887, and get a 3dmark 06 score of 5411. Anyways, i'm planning to do the conductive pen volt mod tomorrow. I'm PLANNING to go to 1.4 volts, but I want to know, can I go to 1.5 on my cooler? Or do I need water and whatnot?
Any help would be appreciated!

[eric003]

what is the temp under load? cause honestly temp during idle doesn't change that much between air and water... I mean i have water on my gpu, and it idles at about 38-39,
but under load it is only 42-43. I have mine Oc'd to 575/825 I'm actually quite impressed that you Oc'd your ram so far.. I guess though u kinda have active cooling on the ram.. do u have heatsinks on the ram also? I just have copper heatsinks on mine, but there is no real airflow on them.

[pyro786]

I just have those little blue heatsinks that came with my zalman.
I actually oc'd my ram this far with a stock cooler, before I got my vf700!
Anyways, so load temp. Should I measure load when playing a game, or load when running 3dmark06, because they seem different.

[Qubix]

I've seen people do 1.4v with stock cooler but temps tend to rise quite a lot and they suplement cooling with additional fans blowing on the video card to help airflow. 1.5v with a zalman is doable but I would highly recommend that you have good airflow to the video card to help it maintain a good temp. These 7900GT's can take a lot of heat though.

I recommend doing the 1.4v mod first and see how your temps go and compare with your stock load temps and see if you have room to play with 1.5v mod. Better safe than sorry.

[pyro786]

I guess I'll go 1.4. I'm hitting 56 max load, on firefly forest, which is the hottest 3dmark06 test for me.

[bignick]

I would stay with 1.4V. Your temps will climb at least 10 degrees idle and load after you voltmod. I have mine clocked at 650/1800 and it idles at 47-48C and loads at 60C. At 1.2V and 500/1500 temps were 38-39C and loaded at 50C. I have a NV silencer and better than average case cooling. Just give you an idea on actual temps.

[wellnessoc5]

I was just getting on to ask my question when I saw this one, I just got my 7900GT, my watercooling system is in my sig. What would you reccomend? 1.3v, 1.4v, 1.5v, or 1.55v?

[Metr0]

you are good for 1.4v with your cooling.

i think the next step from 1.4v is 1.55v (read it around here).

[wellnessoc5]

well..... I did it at 1.5v, and it's running fine @ 720MHz GPU, 36C

[bignick]

1.5V is really a good voltage for water. I would say 1.6V is max but many have gone 1.7V on water.

[Metr0]

well..... I did it at 1.5v, and it's running fine @ 720MHz GPU, 36C

do you have a pic i have doubts about how that mod has to be done

[wellnessoc5]

What the hell is there to doubt? Just go to radio shack and get a conductive pen(I got mine for $6) look up the mod on xtremesystems forums and perform it. If you mess up, just wipe it off with alcohol and try again. I had to do it two times before I got it right.
PS: USE MASKING TAPE TO OUTLINE YOUR CIRCUIT!!!

[wellnessoc5]

you are good for 1.4v with your cooling.

i think the next step from 1.4v is 1.55v (read it around here).

Why are you giving me advice on this when you never performed the mod?

[Metr0]

Why are you giving me advice on this when you never performed the mod?


i did it but only up to 1.4v

you want a pic?

[wellnessoc5]

Sorry I did'nt quite understand. Well, the 1.5 or 1.4v mod is pretty much the same thing, just connect the points in the middle between D508 & D511

[almstsobur]

I am running 1.5V on air, reached 670 Core, with a Zalman VF900-Cu cooler. max load temps are 66C (26.5C ambient) My idle temps went up 9C or so from 1.4V but my load temps only went up about 5C.

[chas0039]

My EVGA 7900GT was at 39C with 47C under load, with a Zalman 700 and very good case cooling at 500/750 MHz. Ambient temp is 75F. After a 1.4 Vmod I am seeing 43C and 55C under load at 625/800 MHz. Very acceptible for my needs.

[ChristmasGT]

This is a good thread, I just picked up a VF900 a few days ago and I'm going to Volt Mod my eVGA 7900GT with the conductive pen method think 1.5 would handle fairly well for awhile with the VF900 Cooler?