Im in the UK, and if i was you i would have got a 6600gt (much better value than the 6880) but anyways i think you should go for the AMD Athlon 64 3000+ its great value for money (£100) and will overclock up to a 3500+, you could possibly spend the extra £20 on a good heatsink (arctic cooling are good) to keep the chip stable whilst overclocked.
LJ