I have managed to find out that my GPU is a Bestec with a maximum output of 250 W (that's what it says on the sticker on the side). The motherboard is a MSI Boston 1.0, with what I think is a PCI express 16 (am I correct? http://imgur.com/lIAQY ).
NO! Just don't get it. The 650ti needs a 6 pin, and a 250w psu, probably won't have one. Also, even if it did, I doubt the psu could handle that much wattage. Also, new gpu's don't use that type of slot anymore.