Thanks for the reply dude.
Well I checked the PSU (as i said there are two with me Corsair HX1000W and PC Power and Cooling Silencer 750W) And they are starting fine bith.
I Powered up the Hard disks and attached them to Lapptop via a USB adapter and they are working fine (PHEW!!!! THANKFULLY) I have checked with a Multimeter various power pins of the PSU and all are getting volts, the CPU cable is giving 12V in all 4 Slots, so is PCI-E cable, Hard disks one 12v and the other 5v (i think) and the mobo leads are giving 12v, 4(I think) and somewhat similar (forgot ) So I guess the PSU is fine.

Do you think that the Processor or RAM could have cause it?

And for the PSU it was working fine for the past 1 month, then after the swap for Processor it started.

Hmm may be you are right that there might have been a shortage in Board.
One question, please can you guide me to Testing PSU (Other than what i did)

Again thanks for the help.