Need advice on new GPU?

[MarkOne]

to came back to your PSU .... how old it is, PSU lost power with age,

Originally Posted by Raserei408

All depends what games you're playing a lot of. For Crysis, yeah, a 5770's probably not enough for really good frames at 1920x1200. However, if all you're doing is L4D2 it's more than enough.

what is the size of your monitor ? do you own a 1920 x 1200 ?
do you try the difference betwen a 5770 and a 5870, of course not ....
You base you recommendation on the fact you own a 5770 , so it have to be the best card. Peoples who throw $ 400 and more on a GPU are not all stupid..