I'm dealing with a dp700a3B-a01us here that hangs at BIOS splash screen.
I've taken it apart, and stripped it to the mainboard/CPU/heatsink/ram, and it still hangs at BIOS splash. The computer does not respond to the key presses.
Things I've tried:
Cannot access BIOS setup.
Blank screen when any combination of RAM/CPU is removed. The two heatsink fans stay on.
Of two heatsink fans that start at boot, only one remains on when RAM/CPU are seated.
CPU heats up when heatsink is removed. Single heatsink fan speeds up to cool down CPU.
CMOS battery has been disconnected. There are no apparent flash jumpers.
I can report no blown parts, and no smells.
Nothing particular to report as to what happened to the computer before it messed up aside that it was left on for for about two months at one sitting.
No USB devices are connected.
I followed the boot order flowchart and I'm afraid the motherboard may be bad.