How Is The Gtx 750 Better then the Gtx 730 ?
The Cpu In My Computer Is A I5 @3.20
Typically any GTX is better than a GT Version of any Nvidia Card,
GT Series - Any Application that isn't to Video intensive, generally Everyday Applications.
GTX Series - Gaming or Workstation Grade work, at High Resolutions with little to no issue with said task.
I'd suggest getting a GTX Series Video card that doesn't require any additional power to the card other than the standard PCI Express power delivery. Basically to tell wether or not it requires it, is to see if it has Power connectors on the side of it, if it doesn't, then your good to go. If it requires power connectors to be plugged into, you may need to upgrade your powersupply and motherboard if they don't support it.
Let me know if this is what your motherboard looks like without any hardware on it, I may be able to help you out when choosing a new video card or powersupply with the video card.
Link
Best Of Luck!
~Zac's Custom