some of my friends says wen the graphics card is 300 watts thn v need atleast 650 watts of psu else it may damage the components..so am confused of buyin this gt 730 ddr5 2 gb
No... Just, no...
For one thing that GPU is a 30W GPU.Secondly
"650W PSU", "450W PSU", "300W PSU" - these are all just pointless, meaningless numbers. Your friends are spreading misinformation.