I have just been through this all.
I spoke ot Chaintech (Oct 2003) if you have an unmodified board (look
for numbers starting S101 - S103 then you cannot use a 333 FSB CPU.
Limiting you to an XP 2600 (133FSB) if you can find one.
However they will modify it for you for free, well they used to, now
they just exchange it for a version M101 board. (no *** wires
soldered onto it)
The service is excellent i couldn't reccomend them more highly within
a week you will have a shiny new board (boxed with a new set of
accesories) that will officially support 333FSB and take the Barton
CPU's up to the 3000xp. Thats official from Chaintech. You just
exchange it for your old one.
If you still have problems they state the PC must have at least a 400W
PSU and they recommend Dane Lec or Corsair memory.
Best contacting Luc in holland and ask him to sort it.