MTF Epsilon 11 :
dannyboy2233 :
Do you have any idea what size your case is/what the specs of the motherboard are?
Yes. Case is 15.3in (height) 6.9in (width) and 16.1in (length). Motherboard Specs: http://gyazo.com/01ba44514227f9f3beaa41fc2671ba3c
Since your PSU is so small, you will have a hard time getting a great GPU upgrade. What I recommend is upgrading the power supply as well, to a 600W (up from the 300W that it has right now). Then, I would buy (obviously) another GPU, depending on your price range.
~$200-$220- 7870 GHz
~$300- 7950 Vapor-X
~$400- GTX 770
~$500- 7970 GHz
~600+- GTX 780/Titan (although I would definitely not go this high on your computer).
I would try to stick with the 7950.
In terms of PSU's, Corsair and Seasonic make great PSU's. I recommend the CORSAIR Builder Series CX600 PSU, $70 from Newegg.com.
Make sure that there is a slot on the side of your case for the GPU.