So i have overclocked my system for the first time, i did it the "safe" way, increasing the "CPU Frequency" in the BIOS by 1 at a time. It seems like Frequency 200 is 2GHz. So when i reached 220, it was 2.20GHz.

But if i turn it up to 221, then the CPU runs at a clock speed of 1.78GHz.

I was thinking this could be because i use the stock cooling?

If so i need to buy a new cooler (which im thinking to do, a Zalman Fatal1ty should do.)

I am at 37c idle with this one now (the stock cooler)

Mobo: Asus A8N-SLI SE
AMD Athlon 64 X2 3800+ @ 2.2GHz

Thx for help.

maybe your cpu heats up and the cpu/mobo automaticly underclocks the cpu for safety at 221fsb it's multiplier should be 8(original 10). (or it may be Cool 'n' Quiet) i am not sure.

hmm i had the multiplier set at "auto", which makes it 10.

cool n quiet is off.

haha, just got a thing here. the multiplier was set to Auto, which means it automatically adjusts after the CPU Frequency.

i see now it had turned down to 8, and 221*8=1768 = CPU clock of 1768MHz.

Problem solved.

Time to set it manually

Didn't know it can downclock automatically. And why didn't it go down to 9x?

Also, there's no real need to go 1mhz at a time. Just bump it up some 10mhz at a time, until you reach a point where it's unstable. And from there, lower it 1mhz at a time till its stable. Or at least this was the style I did (I went straight to 275mhz, but thats just me). Probably much faster to find a high overclock.

So, if i set the multiplier to 10, and then FSB to over 221, it would work?

when i oc-ed mine, i switched FID to 11X(multiplier) and just raised the fsb til it became unstable...then i lowered it.

Think ill go for CPU Multiplier 10x then.

And raise CPU Frequency (FSB) by 10 at a time.

Thanks for help!

a couple things to note for an Athlon64 processor whenever overclocking...

1. disable cool'n'quiet in the BIOS.

2. change "auto" to "manual" for BUS, CPU multiplier, HTT multiplier, RAM divider, and voltage settings

2. there is no FSB in an AMD64, there is a system BUS (some mobo's still refer to it as "FSB")