When you can afford a new PSU get a reliable one maybe something linus has reviewed these are my recommendations
http://www.dabs.com/products/corsair-430w-builder-series-cx-80--bronze-atx-power-supply-8BV9.html?utm_source=google&utm_medium=ppc%20product%20search&utm_campaign=Components%20and%20Storage%20-%20Cases,%20Cooling%20and%20Power%20-%20Power%20Supply%20Units
or
http://www.dabs.com/products/corsair-500w-builder-series-cx-80--bronze-atx-power-supply-8CDD.html?utm_source=google&utm_medium=ppc%20product%20search&utm_campaign=Components%20and%20Storage%20-%20Cases,%20Cooling%20and%20Power%20-%20Power%20Supply%20Units
I had the same problem as you with my first PC with the same PSU and my PSU claimed to be 600W. It eventually burnt out, stopped working and filled my case with smoke.