650gtx vs 550ti

Don't buy either as both are over priced, buy a 7770 for better performance if you can.

If you want to really go with nvidia, the 550ti is more powerful.

Is neither an option?
http://www.tomshardware.com/reviews/geforce-gtx-660-gef...
As you can see the 7770 is better and it costs the same (for stock clock).
Now depending on actual budget and depending if you are willing to OC or not I'd get these (price after rebate without shipping included).
$110- http://www.newegg.com/Product/Product.aspx?Item=N82E168...
$125- http://www.newegg.com/Product/Product.aspx?Item=N82E168...
$135- http://www.newegg.com/Product/Product.aspx?Item=N82E168...
If possible get the OC sapphire if not I'd just get the $110 one.

I second the 7770, I got mine for what would have been $105 if I did the rebate (I forgot), but still $125 was a great price for it. Not sure what games you play but mine will just about max out gw2 (I think it's my CPU that pulls it down when I throw shadows on high), it'll max out starcraft 2, WoW of course. Those are all the games that I play.

This is the one I bought, it's one of the cheaper ones but it's great, if something locks it close to 100% it usually peak at about 58C with the fan on 55%, but usually it'll stay right around 50C and I won't hear the fan at all:
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Unless you need a Nvidia card the 7770 is a better deal but you can pick up a 550ti for $99 after rebate:

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

I would personally recommend the NVIDIA 550ti as I am using one now. I upgraded mainly for Star Trek Online and it runs on MAX settings pretty flawlessly. You may need to upgrade your Power Supply because the 550ti requires 400W or more. I had to upgrade myself to a better PSU.

Chris

The 550 ti and the 650 have nearly identical performance, the 650 is a little bit better. Between those two, I would get the cheaper one, but if you have an option, HD 7770.

You can also look at 7750's, they perform I think 20% lower than the 7770's, but you shouldn't have to hard of a time finding one under $100

You might want to wait until the GTX 650 Ti comes out on October 9th.
http://www.guru3d.com/news_story/nvidia_geforce_gtx_650... you can wait, the GTX 650 Ti will be out on October 9th.

The GTX 650ti will have very robust performance enhancements, but you must also take into consideration price. The GTX 550ti + GTX 650 both range from $99-$129. The GTX 650ti will range from $180-$200. Quite a price hike.

Chris