I know the make slot1 up to at least P3-700, and I believe that you can find one if you look around enough. If your pc can support up to 800 then you can basically use any P3 Intel processor since it seems your m/b supports coppermine already, so that shouldn't be a problem. Slot1 cpu does cost more than fc-pga if that's a concern.
I recently upgraded my Celeron 450a to a Celeron2 566 that I o/c'd just fine to 875mhz by using the 103mhz bus speed allowed on my AOpen m/b. It's much faster, but only comparable to about a P3-600 or 700 in most games. But I bought this RETAIL cpu for only $71 at buy.com. This is matched to an AOpen fc-pga converter card for my slot1. Don't worry about "slotkets" - just buy a name brand one (Iwill, MSI, etc) and you'll have no problem. They cost about $15-20. Total cost was $100 instead of $200+ for full P3 700-800.
As far as your P2-450 o/c - it already runs at 100mhz fsb. You could try faster bus speeds if you m/b permits (which I doubt it does). Even if you do you won't be able to gain enough speed to notice. Better off buying a new cpu.
Facebook
Twitter