O/C Barton 2500+/A7N8X-X

I have recently purchased a new rig and would like some help extracting a little extra performance. The system is as follows:

AthlonXP2500+
Thermaltake Volcano 11 HSF (with adjustable fan speed control)
Asus A7N8X-X mobo
Sapphire ATI Radeon 9600pro (currently stable at 499/344)
AOpen H600B 300W ATX Tower
2*256meg DDR400 PC3200 Kingston RAM

I've tried o/c it by just changing the multiplier and leaving the fsb at 166 but it won't allow me to select 13x - if i do, it sets the multiplier to something ridiculously low and runs at 800 odd Mhz!

I've found that if i up the fsb (currently at 184) then obviously i can hit higher overall speeds......Currently running at 184x11.5. Temps are not a prob atm and at idle its around 28-30.

My question is, should i keep raising the multiplier at this fsb speed (to say 12 or 12.5) or should i raise the fsb (closer to 200) and drop the multiplier to 11 or something???

Any help is much appreciated

only the kt400 boards can access multipliers higher than 12.5

Definitely bump up the FSB higher...mine is at 200 right now (3200+ equiv 200x11)