Replacement options - need advice

Ok, so I just finished a nice new i7 build but kept my old pair of 8800GT's in order to save a few bucks.

Now I have the opportunity to upgrade those 8800's but I only have about $200 to put toward a replacement card.

I was considering the EVGA GTX 275 or the Saphire 4890.

The board I have supports both SLI and Crossfire, so a second card upgrade later would be possible with either choice. My intention is to upgrade again with a second card by the end of the year.

I don't have a preference between nVidia or ATI, I just want to know which of these two cards is going to be the best choice based on the following:

- Performance
- Upgrade scalability (SLI/Crossfire)
- Gaming Support (Drivers)

Keep in mind I am not asking which chip manufacturer makes the better card, I am only interested in the comparison of these two cards OR any similarly priced card with compatible performance and support.

Sure thing, here is the machine I just built:

COOLER MASTER RC-690-KKN1-GP Black SECC/ ABS ATX Mid Tower Computer Case
ASRock X58 Deluxe LGA 1366 Intel X58 ATX Intel Motherboard
PC Power & Cooling Silencer PPCS750QBL 750W ATX12V / EPS12V
Intel Core i7 920 Nehalem 2.66GHz LGA 1366 130W Quad-Core Processor Model
OCZ Gold 6GB (3 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Triple Channel Kit Desktop Memory
XIGMATEK Dark Knight-S1283V 120mm Long Life Bearing CPU Cooler
Western Digital VelociRaptor WD1500HLFS 150GB 10000 RPM 16MB Cache SATA 3.0Gb/s 3.5" Internal Hard Drive
2 X MSI NX8800GT 512M OC GeForce 8800 GT 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Supported Video Card
(i should make this my sig)

I mostly play MMO's, specifically Everquest2, but I also enjoy some FPS like Left 4 Dead and Fallout 3.
I play on a 24" monitor at max res (1900x1200)

Thanks for the help.

i too game on a 24inch screen, it depends if you like to play with AA and AF.

personalty I would get HD4890 as here in the uk at least tehy are alot cheaper than the GTX275 and can bite a GTX285 if overclocked

If you get the right GTX275 it will be faster than the HD4890.

If you want that extra AA and AF enabled on the more consuming games then get a factory overclocked GTX275 or just get GTX280.