Re: Possible Upgrades(Pre-Built)
Welcome to the forum.
To answer you, how much you want to through at it, but mostly what do you want to do with it.
Being intel, you can toss in a better cpu no problems, but to put a decent gpu you'll need a new power supply.
Though, i3 are okay for gaming.
It has a 300W power supply, so you could possible add a gtx960, which will let you play most games decently.
Foldie = i7 950@ 4.0Ghz Gigabyte x58a-ud3r EVGA 970 SC Corsair H100 Corsair hx520 3x2gb OCZ Gold Corsair 650D
Woohoo = L5639 @3.1Ghz EVGA SR-2 gtx 260-216 Hyper 212+ Corsair 1050hx 6x2gb Corsair XMS3 Blackhawk Ulra
Alienware 18 - SLI 770M 4700mq 16Gig