1. Negative on cheap case with 'free' PSU - explosive accident waiting to happen @@
2. Dell 24" would be 1920 x 1080 native resolution
3. Far far better options at that price point for 2 x 2 DDR3 ....
4. You may play modern games on HD 5770 on your native resolution but i wouldn't drop to anything lower ^^
+1 to batuchka, i'd stay away, far, far away from that logisys 480w power supply. Look for an OCZ, Antec, Seasonic,Corsair power supply about 500-550watts. Rosewill makes pretty decent cheap cases, as does Antec.