If you take a GT 650 Ti it would be "a lot" better for not to much money more.
http://nl.hardware.info/vergelijkingsta ... 059-163616
I would take this one:
http://us.hardware.info/productinfo/163 ... ion-1gd5oc
*Sorry for the dutch, but numbers are numbers
And a i5 is good enough for gaming, HT doesn't do a shit whith the most games. (Some exeptions)
But honestly I think 900 is much for this rig included screen. Is it OEM or are you going to build himself?
EDIT: I see it's a OEM, building one yourself you should really consider as a good option...