Why is the 4890 better than the gtx 260 (216)

I am going to buy a video card for about $200 and right now they are on the top of the list. I heard the 4890 is better I dont understand why. the gtx 260 has a little less memory but it uses 448 bit vs the 256 bit on the 4890.. And the main difference that i cant comprehend is that the 4890 uses 900 mhz memory clock vs the gtx 2000mhz memory clock. Im no expert but based on that wouldnt the gtx 260 be better?

my specs:

windows 7 premium 64 bit

AMD Phenom II 940 Black edition 3 GHz

my gay 9500 gt lol

750 watt psu

ecs black editionmobo with one pci express 2.0 X 16 slot :(

full atx case

8 gbs of patriot ram 800 ddr2

2 monitors one 23" lg 50000:1 1080 p (main) and a sony 19" on the side

Regarding the memory, 4890 uses GDDR5 while the 260 uses GDDR3. You cant compare them directly, just look at benchmarks. 4890 > 260.musclesforcier

the 4890 is the better card, looking at benchmarks is the best way to compare cards,

here are some benchmarks comparing the two

fallout 3

far cry 2

left for dead

go for a 5850 and just up it one level for the same price.ColdfireTrilogy