Im upgrading - 8800GT SLi or Phenom

Depends on when the new stepping comes out for the Phenom and if it improves performance. Also, depending on the resolution you play at, another 8800GT might not even give you that much benefit.

I'd definitely say Phenom if they fix the problems with them buy the time you are ready to upgrade.

Since you are thinking about going SLI, then your upgrade would be for gaming. A new Phenom won't make much, if any difference at all for gaming over the 5600 X2 you have now. Another GPU in SLI won't make a lot of difference either unless you run at very high resolutions..........

what should i do? if i wasn't to do sli or phenom? my budget would be $300

Totally depends on the games you play and resolution you play at. GPU intensive games, high resolution, fsaa ...SLI will help the most. But in a CPU limited Flight Sim or RTS game, the CPU would help more. Also consider games like Oblivion in which some areas (outdoor foliage) are very GPU bound and other areas (in towns, lots of NPC's) are very cpu bound.

I'm with these guys wondering why you want to upgrade? If I had to choose for general gaming I'd rather have the SLI route, especilly on a 22" or 24" LCD. But really, then you'd want a faster CPU to best take advantage of the dual cards. So if both upgrades are out of the question, you may want to just reduce settings a bit, keep gaming, and put that $300 toward a rainy day or your next build.

You would likely need a new Power Supply if you upgrade the graphics card. I don't think the current 520W will be sufficient