subhransu :
Corsair cx450 is out of my budget
The Intex 450W isn't actually a 450W. With only 18 A on the +12V rail, it's just barely a 200W PSU, for all intents and purposes, and that's if it had amazing parts, not with the garbage we see in these types of fly-by-night firestarters.
Honestly, if you don't have the budget for a GPU, CPU, and for a PSU that doesn't risk destroying that GPU and CPU, you don't actually have the budget for the GPU and CPU. I'd suggest waiting to buy until you can get a competent PSU that can safely power the equipment you buy.