Hello.
I was tyding up a w10 installation this morning and I shut down the computer when I was going for lunch. This afternoon the computer refused to power on even if there is a lit green led on the motherboard. Things I have tried.
1. Trying a different psu.
2. Shorting the two power switch pins with a screwdriver.
3. Testing a different memory module (ddr3)
4. Reset cmos
5. remove cmos battery for 1h
I suspect mainboard may be dead.
Any ideas?
Have you gone to a minimal configuration? All peripherals disconnected. One DIMM, no hard drive, etc. PS/2 keyboard and mouse if you have them. The absolute minimum to get into the BIOS setup. If you can't get into the BIOS setup then, I'd be pessimistic.
The only other thing to try would be the BIOS recovery. (See the manual.) It seems highly unlikely that the BIOS could be corrupted, but it's the only thing I can think of that wouldn't involve a failed motherboard.
Good day.
There is only one harddisk which I already disconnected. There is only one stick of memory (I remember to have tried both ram slots). Keyboard is ps/2. Mouse is USB. I have even tried without keyboard/mouse.
I could unplug all mb connectors (hd audio, usb headers, etc) and try again.
By the way. I cannot perform a BIOS recovery because system doesn't power on.
Does the MoBo has a speaker so you can hear the POST beeps?
A PS has mainly:
+3.3V
+5V SB
+5V
+12V
You may have one that is not working.
Did you checked the 12V CPU connector?
Does the fans run?
The mainboard has got no speaker, so no beeps. I have already tried two different PSUs. Anyway, I have ordered a new mb, cpu, memory to replace it. Just waiting for it to arrive.
THE PLOT THICKENS!
When I connect power to hard disk the new mainboard doesn't power on. Without hard disk connected it works.
Why?
The hard disk might be the problem. I have come across something similar. Did you try the b75 mobo with no peripherals attached?
In addition, you can probably get a little speaker thing like this:
https://www.ebay.co.uk/i/29262867685...iABEgI2OPD_BwE
Yep. I have just tried it, totally naked on the floor. I just connected the PSU connectors. Green LED lights on but no power on (using a screwdriver to short the two relevant pins (power button on F_Panel).
In the interim I have ordered a new case too. I was using a very old one and it might be damaged, who knows.
Quote