OverClocking in Linux. How much GF2 can take?

[AnXa]

I have old GeForce 2 GTS(Asus V7700) I bought couple years ago. I haven't much OverClocked it since I am just happy when everything works. But now I bought today a FX 5700 card and while waiting it to arrive I started to think how much I can take out from GF2. okey. In Windows I got these clocks and it was terrible snowstorm. It definedly was the highest clocks (Core: 230 Memory:420)

I think that normal clocks are 400 for Memory and 200 for Core

Now. Cause I am a Linux user I wanted to test OverClocking functions also in Linux. Since I don't know anyother overcloking tools but NVClock I started using.

I write down those clocks to and started benchmarking in Ut2003. I didn't saw any on this snowstorm and no graphic clises cause of memory.

So I decied to OverClock some more, and more and still little more.

Now I have Memory speed in 450MHz and Core Speed 250MHz and I still dont see any problems in screen like snowstorm and graphic clises. (It means that GF2 OverClocks better under Linux, is this true?)

Does anyone have more expericence than I do about OverClocking in linux. Is this dangerous to card to have clocks this high?

Or can I OverClock some more? Until I see Snowstorm and other graphic clises that are cause of too high Clocks in card also in Linux?

In both cases . Under Windows and Linux I do have been newest drivers. And my benchmarks are based on Ut2003, ut2004, Quake3 and under Windows also to 3DMark2001SE and Doom3



EDIT: I found out that under Linux Ut2003 can handle Core Speed: 257 MHz and Memory Speed: 458 MHz

And that is limit since after that I got huge numer of graphical clises...

[Thunderbird]

If it is really a GF2 GTS then the default speeds are 333MHz for memory and 200MHz for the gpu. Further the memory is the bottleneck, so overclocking the gpu itself doesn't help much.

If the default memory speed is indeed 400MHz then I don't see much problems with 450MHz else if the default was 333MHz I would worry a bit more as this is about insane overclocking then. (10-15% is useally "safe")

Basicly overclocking works like this. On the card there are some register values you can change. Those values are the inputs of a so called "Phase Locked Loop" (PLL) which creates the actual memory or gpu frequency. The overclocking algorithm creates those register values which control the PLL. You can get a similar clock frequency using dozens of different calculations. The calculation used in nvclock is a little different than the one used in the nvidia drivers which causes the differences. (note that the nvidia drivers also do a little more to stabalize the clock which nvclock doesn't)

[Antti]

I don't really think you can break a video card easily with overclocking, as long as it has at least some cooling (like the basic cooling it came with). If you clock it too high, your system crashes. If the card overheats, the games start to crash (usually back to desktop). In any case, the card gets cooler again after this.

But I take no responsibility if you manage to fry your card. And congratulations for quite high overclocking results. If the games don't crash and there's no graphic bugs, the card is not running too hot but is working very well.

[AnXa]

Thanks for info. I am going to stay here where I am at this point (or little below). I am still just wondering however why I can get better results and higher clocks under Linux than under Windows. Maybe it is just about the differences how these systems work.

[Thunderbird]

As I said before it is the difference in the overclocking algorithm. For some cards my nvclock algorithm is better and in some cases nvidia's code is better.

[LavaDevil]

That's good OC'ing! Does anyone know the GPU and mem speeds for the FX 5700/Ultra?

PS: How did you get NVClock working? Only the CVS version has good FX support, and it doesn't want to work, complains about segfaults.

[Thunderbird]

At what stage does it segfault? Try to replace "gcc" in the makefiles in src/ and src/backend with "gcc -g" to compile nvclock with debug info. Then run nvclock like this:
1) gdb ./nvclock
2) run -s
3) bt (when it crashes)

[chrismortimore]

A 10Celcius increase in temperature halves CPU life apparently, so any overheating is bad :P

[Thunderbird]

But the life of a cpu is useally 20 years, so that half cpu life is not bad

[chrismortimore]

Granted, but if its meant to run at 50C and ends up going silly at 90C, thats like 20/(2^4) years, which aint much :P

[AnXa]

I got that FX5700Ultra. It is really nice card.