Hello I've been wanting to replace my AMD Radeon HD 7450 for a while now and even more so now that Planetside 2 has launched and my fps in that game is about 10-20 in Big field fights with tons of people on the screen and about 40+ when nothing is going on and I'm in the middle of no where. I've also had problems with other games as well such as GW2.
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=2951332
^ That's my exact computer with all the specs and what not, I'm not really computer savvy but I've been looking at some of these
http://www.newegg.com/Store/ComboDeals.aspx?ComboStoreID=25&name=Video-Cards-Power-Supplies
would it be best to just buy it as a combo or pick my PSU and GPU individually?

http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=2951332
^ That's my exact computer with all the specs and what not, I'm not really computer savvy but I've been looking at some of these
http://www.newegg.com/Store/ComboDeals.aspx?ComboStoreID=25&name=Video-Cards-Power-Supplies
would it be best to just buy it as a combo or pick my PSU and GPU individually?