I built a new system about a week ago that has been performing fine. Last night I put the computer into sleep mode and this morning it seems dead. Won't respond to the power switch, no matter long long I leave it pressed in. I haven't opened the case yet but peeking through the grilles for the fans I can see that LED lights are on the MB. This is true even when I disconnect the power supply cord. Specs for the system:
ASUS M488TD-V EVO/USB3.0 MB
Phenon II X4 965 processor
4 sticks of Corsair TW3X4G1333C9A
I also have a Logitech wireless keyboard/mouse combo with the latest version of Setpoint
Is there any chance this is a software/BIOS problem relating to sleep mode? Or do I probably have a failing hardware component? It seems very odd that the MB lights stay on even with the power supply completely disconnected.
If you disconnect the power cord from the power supply, the PC should completely shut down regardless of the state it is in although there may still be residual power in the system in the capacitors on the board. You need to wait a few seconds for all the power to drain from the system before plugging it back in. If the PC doesn't power on at all at this point, you have some sort of hardware issue.
If you have a spare power supply you are sure that works, try using that one and see if the system boots up. If it does, then your original power supply may have died. If it doesn't, the problem can range from the motherboard, ram or CPU.
Alternately, if you don't have a spare power supply, disconnect all the connectors from your system and on the ATX connector to the motherboard, short the green wire with any of the black wires. If the power supply fan spins, most likely the power supply is fine and once again the problem lies in your motherboard, ram or CPU.
If it comes to this point, disconnect everything but the core components and try booting with 1 of each of your rams to see if its a defective ram causing the problem. If you have any spare good ram, you may as well try them too. If it still doesn't boot, you've most likely got a dead motherboard.
Pretty bizarre. After disconnecting everything but the power cord (preparing to open up the case) , disconnecting the power cord caused the leds on the MB to go off. Hooked everything up again and it booted up and seems to be working normally. I would think that would let all the hardware off the hook but the MB, and it might be some software/BIOS glitch related to sleep mode. I'm not sure I trust the Logitech drivers although it seems far-fetched they could wreak such havoc. Strange stuff.
This is usually the number one fix for almost all electronics. A complete power off unplugging cords, etc and let it sit for a while then plugging everything back in.
The cause is usually power flickers or fluctuations in the power grid. Invest in a UPS for your computer, you won't regret it. Just make sure it has enough wattage to power your system or else the alarm will sound all the time.