my pc will not power up after installing a faulty power supply

[red040281]

my pc will not power up after installing a faulty power supply ive put the old one back in now all that happens is the blue power light comes on all fans start cpu,psu,case,graffics card that's it there is no noise coming from the hard drive and nothing coming up on screen ive removed all components cables ect and tried to fire it up with just one stick of ram and onborard graffics but still nothing comes up any ideas

 

[tiny voices]

You may have fried the RAM/Motherboard/HDD with the poor quality PSU.

 

[red040281]

I was thinking along them lines myself cpu/motherboard/ im hoping its not the hard drive if I try and start the pc without the hard drive it does exactly the same with no boot menu or bios info