Anything below a 5850 won't outperform your current card. Even the 5850 won't outperform it by much. And I agree, hold off. Right now, almost nothing uses DX11 and it will be a while before games really start using it.
The HD 5850 will outperform the HD 4890 nicely, but it will be hard to find one in stock. Personally at this point in time I would almost recommend just adding another HD 4890.
You're better off adding another 4890 to run them in CF. Sure a 5850 would be a pretty decent trade up, but availability is pretty bad, two 4890s would generally be faster, and it will be a while before you need DX11 by which time availability of DX11 cards should be much better.
You're better off adding another 4890 to run them in CF. Sure a 5850 would be a pretty decent trade up, but availability is pretty bad, two 4890s would generally be faster, and it will be a while before you need DX11 by which time availability of DX11 cards should be much better.
Two 4890s are loads faster than a single HD 5850. The thread I linked to compares them against the HD 5870. We do need to keep in mind he may not have a CrossFire capable motherboard or good enough power supply however, in which case the 5850 is his next logical option regardless.
Message edited by brockh on 11-14-2009 at 11:22:43 PM