Here's what I see in your build:
A decent CPU that would get the job done for sure.
Not enough RAM for some games but good enough for most, especially since you are on a budget.
A crappy video card that is worse than my card. My card is 3 years old and wasn't the best even then. You will not be gaming on this. If you need to save more money by sacrificing other parts in order to get at least a radeon 4670 (or 5670 if you want DX11) then sacrifice your CPU. Go with the cheapest Athlon II x2 you can find. It will get the job done. Of course, I also have to ask the resolution of your monitor. That makes a difference too.
ok so I'm swapping out the i3 for amd and upgrading the gpu to
Club 3D Radeon HD 5770 1GB - 256-bit, 850MHz Clock, 1024MB 128-bit GDDR5 Memory 4800MHz, 800 Stream Processing Units, 400MHz RAMDAC, Dual DL-DVI, HDMI, Display Port 2 Year Warranty
will a a standard OEM 400w psu be able to handle it?
nvm, 450 Watt or greater power supply with one 75W 6-pin PCI Express® power connectors recommended
Yeah. If you don't want to spend more money on a new power supply, the best video card that needs nothing more than the power the PCI-e slot provides is the Radeon 5670. It performs better than the radeon 4670.