Is there anything i can do before building a new system?

1.5GB DDR RAM

300W PSU

intel D101GGc motherboard

Vista Home premium

acer 19" 1440x900

bought in late 06 when old pc (W98) broke, it's a modified eMachines T5048, i added the gpu right away,ram after that

I would add more memory, but DDR is expensive, and i'm building a new system over the summer, and i was curious if i could use any new components in my current pc before i have everything bought for the new system

I'm getting a 4870 when it comes out, but i would need a bigger power supply, and I;m not sure if i would want to put that into my old pc because it looks like it would be complicated to replace one.

Other than that, my mb doesn't support Core 2, so that sucks.

Any suggestions?