I have a quick question about OC'ing video cards

[hootpie]

Or do you do one, then the other?

Also, does anyone know what kind of speeds I can get with an eVGA 256MB 6800XT PCI-e with an NV Silencer Rev5? It's at 325/600 right now...I'm going to try to get 375/700 if I can.

Should I bump it up 5-10% at a time?

Edit: How effective/reliable is CoolBits? I used "Detect Optimal Frequencies" and it went from 325/600 to 432/815 with only a 4 degree increase in idle temps. I still haven't installed the NV Silencer either. 3dMark06 went from 1452 to 1909 and temps after the benchmark were around 66C

 

[RallyMaster]

I usually take mem up first and then do core.

 

[hootpie]

Originally posted by: RallyMaster
I usually take mem up first and then do core.

So bump memory 5-10% and test it with a game until I reach the highest stable OC, then do the core, correct?

 

[BonzaiDuck]

This aspect of over-clocking is the weakest to my understanding, and I've attempted it before with less success using Coolbits on an nVidia AGP card.

What I have learned recently, however, provides a caveat of defiance to cautions many have made about fixing your AGP/PCI speed ratio in BIOS before running an over-clocked system.

On an AGP-based system, the AGP/PCI frequency ration is about 66/33. Adrian "Rojakpot" website, in its BIOS setting database, notes that you can run this setting up about 10% without endangering your hardware -- to a setting of about 73/36. As long as this is set as a fixed ratio and you do not leave it set to "Auto" in the BIOS, it should do no harm, and you have effectively overclocked both the AGP and PCI buses.

 

[Mogadon]

I used to use coolbits, now I use rivatuner, I switched to rivatuner so I had the ability to unlock the pipes and vertex shaders on my 6800GS, you can only do that with the AGP version though I think.

Download coolbits and install it. Then go into your video cards settings (right click desktop>properties>settings>advanced) and you'll see a new option for overclocking. Go to that and use the coolbits automatic overclocking feature, usually with coolbits it is conservative in these settings so you'll still be able to push beyond that later. Download 3DMark and run it through watching for any artifacts (errors in the onscreen graphics that you know shouldn't be there, if you see 'em you'll know ...).

If you have no artifacts, go back to the overclocking and up the overclock a bit until you start getting artifacts and then back down a little. Once you have a rough knowledge of the limit you can play around with the mem and core settings seperately ... that's what I do anyway.

Overclocking your graphics card in this way is safe as long as you don't set something totally wild for the mem or core. Keep an eye on the temps but they should be fine as long you have good cooling, personally i've never needed an aftermarket solution to overclock a video card although I run the Zalman VF-700 as it's quieter (it does cool better too).

 

[hootpie]

^ great post, thanks. Right now it's overclocked to 432/815 at around 65C...it says the threshhold is 115C, but what's a good idle temp that I should stay around?