I just did a lot of research and here's what i came up with. Note that i already have a 300W PSU, and a 1 TB HDD. http://pcpartpicker.com/user/ThroneOfThunder/saved/#savedbuild_605899
The AMD build will give you much better performance in game. Even besides that, the 300W PSU wouldn't power the 650ti.
Which amd build?
Appologies. I was only checking out the top two. The Ivy Bridge Core i5 ATX and the AM3+ mATX Phenom are out because the PSU aren't strong enough to support the system.
I'm caught between the FM2 Athlon mATX and the AM3+ mATX FX
The FM2 Athlon mATX build will give you more FPS in games, but the 460W PSU might be pushing it.
Jordi is right about the PSU. The best thing to do is double-check the spec sheet for a PSU you want to buy -- I think Seasonic's G series is good, check Jonnyguru for reviews -- and look at the 12 V current it can provide. Let's say your processor's TDP is 125 W and the 7950 needs 200 W additional. With the hard disk, let's say 360 W on 12 V. 360 Watts is 30 Amps, and my 500 W PSU (CX500M) can provide 38 Amps on 12 V (there's a sticker on the top).
It's probably good to make sure your expected continuous current draw is no more than 75% of the rating, so my PSU would not be ideal for delivering 30 Amps @ 12V continuous. It would run a little warm. I am not sure but I would bet a Seasonic G series 600 W would provide 40+ Amps on the 12 V. Besides, the 360 Watt number is a guess. You want to find out what the TDP of your CPU and GPU are.
Inexpensive PSUs sometimes can't provide their rated power, or if they can... not for very long. They overheat or shut themselves down.
Your Phenom build is going to be have the highest performance for many games, because it includes the 7950. I don't think the 4-core Phenom will "hold back" the 7950... maybe someone who knows more can say for sure.
I would recommend buying RAM in pairs, so 2 X 2GB for 4GB total, or, 2 X 4GB for 8 GB total. These are dual channel systems and you'll get significantly better memory performance. Plus, buying RAM in "matched pairs" helps reduce chances of problems.
Finally, be careful with the motherboard's power delivery. Cheap motherboards skimp on how much power they can deliver, and you want this motherboard to work with any AM3+ including the 8350, so you can upgrade later if you want to. On a $55 motherboard that's my biggest concern.
Thanks a lot :D i just rolled in PSU for all builds now.
Thanks :) and yeah i did a lot of checks on all the mobos i added, and i am planning on getting another ram after the pc is built, so i am getting just one now, and i just updated the builds with PSUs.