Vashyo on 12 May 2011
I'd pick Sapphire Radeon HD5850 Xtreme over that 550Ti. It costs about the same and has more processing power making it way better option. If you're thinking about crossfire then you can get two of em and it should completely annihilate the 550ti SLI.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814102932&cm_re=5850_xtreme-_-14-102-932-_-Product
Out of stock from Newegg atm though.
Review with benchmarks: http://www.kitguru.net/components/graphic-cards/zardon/sapphire-hd5830-hd5850-xtreme-edition-review-crossfirex/
It's also slightly better card than the 6850
