Which card to upgrade to?

Hi
I am thinking on upgrading my graphic card to a radeon 4830 or 4850. However my system is not so new and i dont want to wast money on a card that my system is holding back. I currently have:

E6600 2,4 ghz core duo
Asus x38 formula motherboard
6 gb Pc8500 corsair dominator ram
500 MW earthwatt PSU
innovision geforce 7950 gt 512 mb

Would this system hold the 4850 performance back?

Another +1 for the 4850. That's a great card for the price.

Thanks for the reply.
yes I know that it ought to be easy to get it up high, especially with all the OC features my motherboard provide. But how much more performence would I expect to gain? Cause I am still only a student and can only afford to upgrade/replace components twice a year or so and if the gain vs risk is low then I think I can manage until I can afford to really test it through.
Also I have 4 ram moduls and because of that they can only run with 800 Mhz and not the 1066 Mhz. Guess I could tamper with that but I do not know how to

^ Ok then it's fine to upgrade to the 4850.

OCing will only take out about 1 year off the life. Usual non OCed life is only 7-8 years imo. By the time your CPU dies the tech will be history. You can gain ~25-30% performance in all/most apps if OCed.