Yes, the poor quality PSU will cause the problem, also it may kill your MB or other parts too. Buy a brand PSU.I use gtx 750ti pair with i5-3570 with some craptastic psu.
Does it really crash because not enough power?
That model dont really available here.CX450 would be a good budget option.
SILVERSTONE STRIDER ESSENTIAL 500W 80 PLUS 230V EU POWER SUPPLY - V2.0CX450 would be a good budget option.