Debating on new system or upgrading

I have about $1000 dollars and I will be upgrading my computer.

Specs:
AMD 64 3000+ at 2.75ghz cpu
evga NFSLI 41 mobo (skt 939)
1gb 512mb *2 ram
200gb harddrive
2* 7900gt at 680mhz core 1850mhz mem

I want to know if It would be better to upgrade this computer or build a new core 2 duo computer? and If I should upgrade this computer what should I upgrade?

Thanks...
p.s. I will be buying a new dx10 card with that money also so consider that.

Well, you could buy a new Core2 system, but it would be cheaper just to upgrade and not a bad system. I would for now upgrade to 2GB of RAM and move to AM2 in December when 65nm AMD CPUs are available.

I wouldn't waste a penny on DDR memory. DDR-II is phasing out DDR Memory. So as it stands there's no reason to upgrade your rig. Your CPU is ample enough (especially at that speed) and the rest of your specs should not be touched unless you oprt for an AM2 or Core 2 Duo.

If I were you, given your budget, I would wait for the fall... and see how things play out. Don't waste any more money on this rig.