Max 6800gt OC with water cooling?

[mgoode]

As wait a month for my silverprop Fusion HL to get here. :bang head What is the typical increase people are seeing after adding a wc block? My highest stable core on air for benching is 432mhz. I was hoping to hit at least 450 on the core. Is that reasonable with water cooling?

[Enigma422]

450MHz on a GT might be asking to much on water cooling unless you flash your bios to 1.4V, but some GTs don't respond well at 1.4V. 432MHz on air is pretty good though.

[mgoode]

my thought is if i can get 432 on air stock cooling, then i should be able to increase that with a good water block and some AS5.

[Mhypertext]

no just because you make the core cooler does not make it over clock any higher

the need to cooling is when you volt mod it to reach a higher core

[Enigma422]

no just because you make the core cooler does not make it over clock any higher

the need to cooling is when you volt mod it to reach a higher core

Beat me to it, went to check the OC database in the sticky above to see what people are getting to give mgoode an idea of what to expect.

mgoode, like I said in my original post if you are willing to risk your card and flash your video BIOS to 1.4V you will most likely not reach 450MHz, and not all GTs respond well to higher voltages. Quickly looking at on the mbently's database (http://www.mbentley.net/oc/oc_forum_geforce_survey.html) it looks like your max speed is at the high end of what GTs can clock to at default voltage. I wouldn't expect more. The graphics card in my sig reached 450MHz with the BIOS flash but was not stable. At default voltage my max speed was 420MHz, but was ocassionally unstable.

[mgoode]

thanks gentlemen, my card is idling around 56c now and can get as high as 80c under load. I'll post results when I get my Fusion HL.

[mustrum]

Most likely nothing will change. Just a hint: Cool your power converters. If you intend to flash to 1.4v (wich i don't suggest) you have to actively cool the converters or you have a dead card after a few months for sure.

[mgoode]

Ihope the temps will change. I am going to sink the ram with ocz bga ramsinks, where are the power converters located?

[arctic-k20]

well im not sure how common my o/c experience is but my 6800gt's hated 1.4v - would throttle right back and give worse performance than stock...

on 1.3v they will do roughly 435/1130 max on water (keep in mind this is sli and that in itself lowers your max o/c)

my idle temps are 29c and full load is around 38~40 roughly...

i cant compare to air cooling because the cards went straight to water....

on 1.4v coolbits would auto detect a lot higher but it wasnt stable - the stuttering etc would perform worse - so i just settled for 425/1100 (ultra speed) which is still good.

[mgoode]

Beat me to it, went to check the OC database in the sticky above to see what people are getting to give mgoode an idea of what to expect.

mgoode, like I said in my original post if you are willing to risk your card and flash your video BIOS to 1.4V you will most likely not reach 450MHz, and not all GTs respond well to higher voltages. Quickly looking at on the mbently's database (http://www.mbentley.net/oc/oc_forum_geforce_survey.html) it looks like your max speed is at the high end of what GTs can clock to at default voltage. I wouldn't expect more. The graphics card in my sig reached 450MHz with the BIOS flash but was not stable. At default voltage my max speed was 420MHz, but was ocassionally unstable.

Okay making the core cooler did help my overclock!! why did you guys think it would not help.just asking. Temps are 40c idle 47c load
I used to run 80c load. Before wc max core was 432 after max core 455 I am running at 1.3 volts since my gt doesn't like 1.4
3dmark05 = 6180 (http://service.futuremark.com/compare?3dm05=801478 )
not bad fot a gt :)

[baberpervez]

Okay making the core cooler did help my overclock!! why did you guys think it would not help.just asking. Temps are 40c idle 47c load
I used to run 80c load. Before wc max core was 432 after max core 455 I am running at 1.3 volts since my gt doesn't like 1.4
3dmark05 = 6180 (http://service.futuremark.com/compare?3dm05=801478 )
not bad fot a gt :)


That's a flipping awesome overclock!
I am soo gonna get into watercooling now.

[mgoode]

Sounds to me like the GT suffers from power supply problems. Because when one adds water cooling they can usually expect what they are cooling to handle somewhat of a higher voltage. And if all of these GTs cannot handle a wimply 0.1 voltage increase over stock after adding water cooling, then the problem lies elsewhere.

So maybe someone needs to come out with a waterblock for the power converters huh?

Good point, actually since I added the waterblock I havent tried 1.4 volts so maybe I,ll give it a try today.

changed bios to PNY 6800gt rev5 got 1.4 working broke 6200 in 3dmark05

3dmark05 = 6237k (http://service.futuremark.com/compare?3dm05=805462 ) :)