You want to run most games at high settings? You're going to need to upgrade your PSU man.... Its not a big deal and will be worth it.
You MIGHT be able to handle a 4650 if you have enough amps on the 12v rail. What PSU do you have? Name and all that good stuff (or if the sticker on it tells you how many amps you have on the 12v rail...)
opened up the case and gave it a peek most of it was in chinese. The brand appears to be lite on, and it said
+5v and +3.3v Rails 165w max
+12v and + 5v rails 218w max
thats the most I could get off of it
also I would upgrade the psu, but I am spending most my money on parts for the new system so the least amount off money I can spend to get me by till then the better.
I figure I may have to just give in and upgrade the psu but I would like to know if there is anything it can run.