Help me decide between 275/4890

[seba11]

I cant decide which VGA to get, I have a samsung T260 and I'm getting a CM 600W silent. Can anyone tell me the pros and cons of these two cards. Thanks

 

[Amg]

the GTX275 is more expensive, and performaces the same as the HD4890 which is cheaper
however the HD4890s cooler is noiser but can keep the card cool
both cards overclock to the same level, however the GTX260 overclocked can beat the GTX275, in certin situations