System is as follows: E8500 on a DFI P45 mobo 2x2gb ram 7870 GPU 2x SSD 1 sata DVD 2 120mm case fans Old PSU was a corsair HX520 which worked fine but I wanted a semi passive (hybrid) PSU so bought a Seasonic x-750. All set up a couple of weeks back, little LED's on the mobo lit, pressed the power button and nothing. Hmmm. Checked and rechecked all the cables and replaced the 8 pin 'cpu' cable with another one which was included with the PSU. Success! Thought nothing of it until today when the system wouldn't turn on - nothing new plugged in or taken out/changed in any way since successful PSU changeover about 2 weeks ago. Same scenario though i.e. small LED's on the mobo lit - indicating power to the mobo - but nothing when I attempt to switch on, either through the switch on the mobo or the power switch on the case. No fans spin. Checked and recheck all of the connections and no change. So I've switched back to my corsair PSU and everything works fine, which is good to know that the system works ok, but annoying that the silent Seasonic PSU wont boot the system as when it worked it was exactly what I wanted. Any ideas? Is the PSU really likely to be broken - seems a bit poor if so - I don't want to RMA a working PSU, but I can't get it to work. Am I missing something? I've tried it in both hybrid and normal fan modes. Are there known issues with these PSU's? The system all works, so the only issue is with the PSU one way or another. Is there anything I can try? I dont have another system.
