If I remember right, both the 7770 and 7750 are faster than the GTX 650. The 7730 is too slow. The 7790 is a lot faster. A 400W PSU should work fine, as long as it has the necessary 6 pin pci-ex connector some of those cards need.
If I remember right, both the 7770 and 7750 are faster than the GTX 650. The 7730 is too slow. The 7790 is a lot faster. A 400W PSU should work fine, as long as it has the necessary 6 pin pci-ex connector some of those cards need.