It's quite a waste to buy either of those though, they are almost equally bad. You'd get a lot better PC from building it yourself, though if you'd have to choose between the two of them go for the Borg-Q GM4213A simply because it's less shit.
I'm not sure I would buy a new GPU for it as the processor would bottleneck whatever GPU you can buy. We don't even know what kind of Motherboard the PC got, other than it's AM3+. Same goes for the PSU, it might be a 200W PSU leaving you with no option to upgrade regardless.
Save yourself the money, don't buy that trash if you want to use it for gaming. Get help from someone, or read a guide, I highly recommend you build your own PC.
Tomshardware will obviously help you pick out the parts if you would choose to build.
If you really insist on buying one of those though, get a GeForce GTX 750 Ti. That's the best GPU you can get for the money, but keep in mind that there is no certainty that it is even compatible with the PC.