Msi r7770 or msi gtx n550 ti?

[nitsujonix]

i have to make a decision by saturday a friend is selling me his r7770 for 130$ and his n550 ti for 140$ both MSI which one should i get?
just assume that i have the best systems for each card (i am a geek with a lot of desktops...old and new)

 

[greghome]

simple, the HD7770 outperforms the 550Ti

the Hd7770 is on par with the HD6850 and GTX460 with AA on, while the GTX550Ti doesn't even beat the GTX460 Stupid Edition.