It's a socket 939 board. Your only option for getting into a quad core chip is to replace the mobo/RAM/CPU at once. But, you can get a great dual core 939 CPU at a very resonable cost right now (<$100), upgrade your video card. I probably wouldn't reccommend replacing your RAM though, as that will go into the trash during your next upgrade.
If you want to upgrade the entire mobo/RAM/CPU setup, you'll probably be looking at about $150-$250 for the mobo, $80-$150 for RAM and $300 for the quad core CPU. That leaves you with $300-$470 for a new video card...you could almost get an 8800GTX for $470.
So what do you think I should get I would replace them all at once what do you think would be best: Id go for the quad core 2.4ghz, ram and a vid card what do u think tho and i suck at building pcs lol but o well
- reuse the DVD drive, hard disk(s), case (if it's big enough for the 8800 GTX card; otherwise Centurion 534)
- Corsair 620HX (I'm guessing your current PSU won't support an 8800 GTX; maybe you're lucky; what kind is it?)
- GA-P35-DS3L, 2 GB of DDR2-800, 8800 GTX
- E6550 or E6750 or Q6600, depending on how much cash you have left after the above
I think this will be over $1000 but not by that much. You could also keep the 7950GT for a few months and get the 8800 GTX after it drops in price a bit and you've saved more.