Fistfull of questions

[bakes0310]

I currently have a 3700 sandeigo which im very happy with but i beleive it to be holding my x1900xtx back by quite a bit. When i overclocked my cpu to 2.5 i got a 1000 more points in 3dmark03 so that proves to me that the cpu is holding it back. This this leads me to some options:

1. Buy the Thermaltake Big Typhoon 4 in 1 Heatpipe and Arctic Silver 5 Thermal Compound and overclock the hell out of it. I havent upped the voltages yet and my temp is 40c idle so i could possibly get it to 2.7/2.8.

2.Buy a new cpu budget £270 i could get either:
Opteron UP 165 Dual Core San Diego 1.8GHz 2MB Cache
AMD Athlon 64 X2 Dual Core 4200+

What should i do?

 

[Dunky]

Dual core won't buy you much just now, only a handful of games support dual core just now (CoD2 and Q4 come to mind). I'd try with a new cooler and see how far you get. Just keep an eye on the temps (keep under 50c) and don't push the voltage too much (1.55 to 1.6v max).