mux
Striker
Your CPU isn't that bad to be honest, but your GPU is very poor. You'll need not only a higher capacity PSU, but one that is better quality to be able to support a better graphics card.
You're faced with the issue where you'll be spending more on the system upgrade than that system is actually worth.
It would make more sense to save for a new system.
I'm having a hard time finding out which PCIe version it uses, so install GPU-Z here: http://www.techpowerup.com/gpuz/
And let us know what number appears here:
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We can take it from there.
PCI-E 2.0 X 16 @ 16 2.0
Thanks for the advice so far, really appreciate it!