going 775 to x58, should i upgrade 4890 to 5850?

i "have to" buy a new computer every year. i am putting together an x58 build to replace my 775 build last year. i was looking at "upgrading" from my xfx 4890 to xfx 5850 as it seems the 5850 is slightly better (http://www.anandtech.com/bench/Product/175?vs=164. i don't care that it's a little louder, or power hungry, cost is not an issue, but I'd rather not spend it if I'm not going to notice a difference...BUT since I mainly use my pc for Call of Duty, email/internet, photo editing, NO video editing, SHOULD I UPGRADE or just transplant the XFX 4890? thanks in advance!!!

Transplant and save your money for a more noteworthy upgrade.

Well, you would gain DX11, if that matters to you

since i dont even know what dx11 is, transplant it is...thank ED

I went from a 4890 to a 5850 a long while back and it was a rather decent boost in performance. But depending on what resolution and detail settings you play at, it may not give you a very perceivable improvement. Although you can get 5850's for $175 these days I would hold off for now and see what the upcoming 6900's do to the market and what prices they come in at. If you determine that the 4890 is not giving you the performance that you desire, then upgrade to whatever fits your budget.