Hey there people, thought I'd try this forum since I've read a lot of good answers releated to other topics.
Here goes:
I have:
Asus A7N8X-X mobo (max fsb 200) (yeah, I've read all the other posts about this card :-/ )
AMD XP 3000+ Athlon @ stock (the 333 version)
1.5 GB pc3200 RAM
Gainward 6600GT 256mb

For some strange reason, I cant even clock it to the stock 200mhz.
It wont even boot if I dont run it in 166mhz..
With the AMD I have, I cant adjust anything else but the fsb, the multiplier is locked.
I can set the memory timing to 200, but not the cpu.
I've tried to move the "famous" jumper, but no difference at all. http://france.asus.com/products/mb/s...x-x/jumper.htm
What happens if i remove it completly?
I've tried to take it 5mhz at the time, but it wont take it.
I have plenty of cooling and run at 32' idle and 40' work.
There must be a bottleneck or something, but what?
The psu maybe? Its an 360W, but a quality one.
I must have tried 30 different options, but I always fail :-(
Anyone got any good advices?

Its probably your memory.
If the mem is set at 400Mhz effective(2x200)and you up the bus speed
your also upping the memory speed,and its not taking it.
try setting the mem to 333(166x2) and gradually O.C from there.
you'll have to play with the voltages and mem latencys to push it much past stock speeds .
Google it,or search the forum. Theres plenty of info available to you.
Also how many sticks of memory do you have installed? 1-1/2 gigs is an odd number.
If its 3 sticks of 512MB try taking out 1 stick.
EDIT///
Welcome to pimpRig.If you get a chance check out team PimpRig folding@home,your welcome to join.

Thanks for the answer RBIEZE,
I'm kinda suspecting one of the three 512 sticks I have.
Their all pc3200 but the timing on one of the sticks looks crap when I look at it via Everest Home Edition.
Its clocked @ 200 MHz 3.0-4-4-8 ...
I'm guessing it has to go, because both the others clock @ 200 MHz 2.5-3-3-6

Edit: I'll be sure to look at the page, thanks :-)