OCing in SLi

T

Tweakin

[H]ard|Gawd
Joined
Apr 14, 2003
Messages
1,280
Quick question. Is it possible to overclock a pair of cards in SLi? I have never heard otherwise, but I just tried to bump my chaintechs up a little with coolbits and I cant budge them at all in SLi. With SLi disabled, I can pump either card up +35 core and +85 memory. I am thinking maybe it's an issue with coolbits? I can't even get the settings to pass 'test changes' if I drop the 3d clock down -100 on clock or memory.

I am baffled... :)
 
drivers? I think the you need drivers 71.89 and above to OC with SLi... it does work though, but heat is a HUGE issue so make sure you have lots of air on those cards!! or water, or both! see the link in my sig for some sli cooling tips.
 
Coolbits and Sli works fine. I just went from 2x6600Gt myself. Definately use the latest drivers.
 
Hmm I am using the latest 77.77 official drivers on a clean install of windows. It's bizarre, I can't even get the 'test changes' to pass if I drop the cards down to 300/700.... WAY below thier it's stock clocks. Something weird is going on here :confused:
 
revenant said:
ok - how about trying rivatuner or powerstrip? With those they don't "auto clock" so you'll need to be careful and OC a little bit at a time and test, etc...

http://downloads.guru3d.com/download.php?det=163
http://downloads.guru3d.com/download.php?det=169
Click to expand...

OK, I tried RivaTuner and am getting the same results. With either card running non-sli, I can crank them both up considerably and run stable without artifacts in BF2, FarCry, HL2, and with 3DMark03/05 (with improved results). If I enable SLI, I can't up the clock speed at all or the test with coolbits or rivatuner will fail. In fact, in coolbits, I dropped the 3D clock all the way down to 125/250 - as low as it can go, and it still will not pass the test. rivatuner is inded doing the exact same thing.

I uninstalled 77.77, ran driver cleaner, and reinstalled 77.77 and am getting the same results. Could I be looking at some sort of conflict else where? Clearly both cards are in good shape, power isn't an option, all drivers are installed and games are running fine. In fact, I don't really care about the OCing, I was just bored and dicking around... but now I HAVE to know whats up heh :)

Anyone have any thoughts on this?
 
qbackin said:
Absolutely sure both cards have the exact bios rev?
Click to expand...

Yup. I have actually had both cards for some time, since shortly after the 6600GT's were released. They have run great the entire time, no hiccups, great 3dMark scores and game performance. They just won't clock for some reason.
 
Try going back to 77.72 drivers. I can't use coolbits or Riva on the 77's either. Not sure why yet. But o/c's in sli work for me on 72's or older.
 
Slippery said:
Try going back to 77.72 drivers. I can't use coolbits or Riva on the 77's either. Not sure why yet. But o/c's in sli work for me on 72's or older.
Click to expand...

Cool I will give it a shot.
 
It could possibly be your PSU, not enough juice for 2 overclocked cards.
 
qbackin said:
A 480w NeoPower is more than enough for those cards ;)
Click to expand...

Yeah, I don't think it's my PSU. All my other components are pretty top notch enthusiast stuff too, not to mention I don't actually get any problems with anything on my system, I just can't adjust the clock speed on my cards well in SLi.

I tried dropping back to 77.72 today as suggested above, I still can't bump the clock up or drop it back in SLi. I also took both cards out today, put thme into another system (nForce4 Ultra - non-sli) and tested the maz clock on each. They were pretty similair, I was able to reach 540/1085 on one and 536/1100 on the other without artifacts in BF2 and HL2. So, the cards seem to be in working order indivdually.

Anyone else have some ideas? This is officially driving me crazy.
 
You must log in or register to reply here.
Back
Top