hmm, if your not getting any BSOD's its software or bios related. Boot into bios and try setting the HDD mode to IDE mode and see if it boots, AHCI mode some drives might not work and cause a reboot loop, If that don't work then im afraid it might be the OS, Try repairing it with the OS disk.
"It wont even boot the a far, basically I press power button and a second later the pc turns off and then cycle continues"
maybe... try removing the cmos battery to reset the bios? Leave it out about 5 minutes, remove the power plug from your computer and then put it back again. I had this happen to me once too, my PC kept rebooting on and on because of something I modified in the BIOS a few days earlier.