You are definitely on the right track. You have plenty of CPU
, RAM and HDD.
For gaming the most significant upgrade would be a new GPU card. I assume with that current GPU you have plenty of PSU. HD 7970, GTX 680 or slightly faster HD 7970 "GHz ed."
without worrying about a new PSU. They actually use somewhat less max. power than the 4850 x2. But your old card is good enough I am not sure how much of an felt improvement you get for the money.
An SSD is fine as well. Unfortunately it cannot take advantage of a SATA III interface which will hamper things until you transfer it to a new system. But an SSD is so fast you won't notice until you transfer it to a new system; for now it will amaze you.
You can add a USB3 card/front panel
. It will not be able to deliver complete USB3 performance as the PCIe x1 slot is incapable of it (especially as yours is not the newer rev. 2.0), and I could not find any rare x4 cards that are out there. But it will still be amazingly faster than USB2 with a USB3 device attached. While I linked to the one with a USB3 header on it, I suspect the case (with this card if you get it) will remain with your parents when the time comes.MSINewegg