to OCF!
This is how I started my first overclock so long ago and it's still one of the best guides I've seen. Take a read through it, run some of the tests, and post back with any questions or results you may have.
http://www.overclockers.com/forums/showthread.php?t=391768
I appreciate a lot you reply. I know about all these programs you suggested me and even more useful programs. I don't pretend you be the panacea to my questions. So I think I must be more specific. Of course I already have tried to overclocking my PC, but until know I didn't get stable solutions. However SuperPi and Memtest 86 pass, I my Bios says me update success, but that's no true. Okay, I down from 200MHz to 166 MHz (I have also proved with 183MHz) and from 5x to 4x, so I up the bus until 234MHz say (234x4<1000Mhz, no problem!). 12x is the multiplier, so that I get 234x12=2808MHz (native 2400MHz); I have disabled all the recommended for my mobo i.e. Cool and Quiet, Speed Spectrum, Fast Write Cache, etc.; you know very well this. Further I put CPU voltage in 1.55v+8.3% (this is in red zone), GPU voltage in 1.60-1.65v ( I know doesn't help much, but anyway), RAM voltage in 2.75-2.80v (also in the red zone). Default timings: 2.5-6-3-3-1T (I never have proved with 2T, but I think that's not the problem). But with this parameters my PC hangs playing e.g. Crysis2 or Metro2033. However, if I put in default everything (of course, antialiasing and V-Sinc off) my PC runs like a champ. Paradoxical, don't you? But let me tell you 3 important things (maybe you know these one).
1.- My VC is Sapphire but HIS also released the HD 3850 AGP, so I went to HIS site and I was surprised about its driver (old version and no WHQL) is 183MB, whereas the official ATI driver is 50MB until now, all whql versions; I have no proved the last version 11.3, but I'm almost sure this driver will not work too. I always get a BSOD with these official whql drivers but with the HIS old driver 6.14 (2009) I have not any problem. And this fact is connected with
2.- I know nForce3 ultra 250 doesn't like ATI drivers (ATI2dvag.dll is the main one), so I suspect HIS solved the problem because the size of its driver but, honestly, I don't know.
3.- I also suspect that the main problem overclocking my PC is precisely the old chipset nForce3, a 2004 technology but, again, I'm not sure.
Now you have a wide knowledge about the issue, so I think you can have some good opinions at respect.
A warm greetings for you,
Pedro