Help with picking a new graphics card

[Marvin]

First post, so here goes...

First, current system specs:
Processor: Intel E8400 at 4gHz
Motherboard: ASRock P45-XE
Memory: 8GB Crucial PC2-6400 CL6 memory
Graphics Card: Powercolor HD4890 PCS+ (GPU clock: 960mHz, Memory clock: 1050mHz)
HDD: Seagate Barracuda 500GB HDD, 16MB cache.

My plan is to get an SSD for my OS and most demanding games (Crysis and so on), and get a faster HDD (a Western Digital Black Caviar 500GB).

I will also be getting some faster memory (6GB of HyperX PC2-8500 memory).

My question is, I have everything in place for another HD4890 (power supply is capable - 850W, motherboard has two PCI-E lanes etc), but should I do a CF set up, or would I be better off selling my 4890 and getting a 5850 or 5870? If I get a decent amount for my current graphics card, I'd be spending a little less overall to get a 5850, and a bit more overall to get a 5870. Is it worth it (either way)?

My main concerns about the CF'd 4890 set-up is that the second PCI-E lane is only x8, not x16, and that it isn't DX11 compatible. I guess that two 4890s should be better overall than a 5850, or a 5870, but whether the same could be said for my system, I'm not so sure.

Or am I being daft and there is something else that I should improve first?

Thanks in advance
Simon

 

[TipTop]

My main concerns about the CF'd 4890 set-up is that the second PCI-E lane is only x8, not x16

It's not a problem: http://www.techpowerup.com/reviews/AMD/HD_5870_PCI-Express_Scaling/25.html

Get another 4890 then sell them both later when DX11 games are more widespread.

 

[Marvin]

Ah yes, it doesn't make a huge difference then...

I'm only using 1600x900 anyway (for now), so according to those graphs, I'll lose 1% overall performance - so no big deal