That's because the GT720 only consumes 9W more than the GT210. It's also compatible with the PCIe 2.0 x16 slot in your PC.
I think that's a fantastic choice.
Well, I think I found my card then.
Thanks McJob.
Edit: I just remembered, Easter is coming up. Usually my relatives get me a little bit of money, so if I get $15 all together I can definitely go for the 730.
I'll see what I get, and then I'll make my choice.