Overclocking nVidia 8600GT

I just completed days of marking. To be frank, 3 more 1500words papers before I am done. But I am DONE with markings. Today is one full day without compulsory classes or meetings. So I am going to overclock my new system. Treating it as an experience, I am going forward with afterburning my $100 card rather than a $225 one.

Overclocking is considered prettty 'hardcore' for gaming. I used (something like 15 years ago) to see friends doing it by modifying the internal clock speed and its pretty scary. Today there are lots of utilities to help you and it looks more manageable.

I go for websites recommending utility and found – Rivatuner. Can I trust the post? I am not sure. But I see the same utility recommended by another post, which is enough to tell me that – even if its not the best, at least it works.

Following the guide on 3Dguru, its pictorial guide and detailed step by step instructions make it easy to follow. First is to setup some fan speed launcher. I do not know why but it must have to do with the heat produced in overclocking? Next is to overclock the chip. There are two clear parameters: memory frequency and core frequency. I am not sure which is the 1000?Hz referring to. But what will be will be.

The pdf that accompanied XFX 8600GT suggested overclocking memory first, at 5?Hz at a time. 3Dguru did not mention, but showed an example of overclocking to what other users have achieved. I followed the pdf’s approach. It looks safer.

I did, but did not. I followed the incremental approach, but not 5?Hz at a time. More like 10-20, larger at the beginning, and smaller after a hundred or so. But 3dguru and pdf suggest having a video benchmarking utility will be nice. I downloaded something which I conveniently found – Video Card Stability Test (VCST).

Now I am able to start the process of overclocking. I raise the memory frequency gradually, while I am tempted to do both at the same time. I can probably raise a bit without getting near ‘instability?’ I raise the core frequency by 30 as well. But that’s it. I continue to focus on memory clock.

VCST suggested stress testing between 10-30 mins. But if I am going to do it at 5?Hz at a time, its going to take forever. Benchmarking only takes 3 mins. So I did that instead of running test (Start) at every change.

My system finally ‘hangs’ at memory clock of 969. I was a bit freaked. But reset the system ‘logically.’ It was fine. It restarted as per normal and reset to default clock speed. So I use the previous stable clock speed of 951 and ran the stress test (Start) for slightly more than 10 mins.

Next, I did the same for Core clock speed. It hangs at 73?. I restarted the system at set the Core clock at 721. Then I ran a stress test for 20+ minutes. Every works fine for the 20+ minutes.

End results: Core 721, Memory 951.

I am still testing the system by running the stress test for several hours.

Rig:
MB GIGABYTE GA-P35-DS3L P35+ICH9
XFX PVT84JUDD3 8600GT 256MB
CPU INTEL|C2D E6550 2.33G 65N 4M
MEM 1Gx2|KST DII667 KVR667D2K2/2GR