Computer will not shut down

I recently built my fourth computer with the following components:

Case: Thermaltake Soprano Mid-Tower VO900M1N2N
MOBO: ASUS Z-87 Deluxe/Quad
CPU: Intel i7-4770K (Haswell)
Memory: Crucial Ballistix Sport 16GB Kit (8GBx2) DDR3 1600
PSU: Cooler Master Silent Pro Gold 800W
HD: Samsung 840 EVO 1TB
GPU: ASUS Radeon HD7790
Logitech MX3000 Wireless Keyboard & Mouse Combo

The operating system is Windows 8.1 Pro (clean install on the SSD). The system is so fast and awesome that it refuses to shut down. It makes no difference how I shutdown, it restarts in about 3 seconds. I have to physically cut power to the PSU to shut it down. I have updated all the device drivers and have the latest BIOS (version 1707) according to the ASUS website. I have tried all the suggestions on the Eight Forum website for Windows 8.1 shut down issues.
As a troubleshooting measure, I also did a clean install of Windows 8.1 (not Pro version) on a 250 GB WD HD without the MOBO and GPU drivers and booted with only this HD (all other storage devices unplugged). The same problem persists so I believe it is a BIOS setting or a motherboard problem. I am using the default BIOS settings without overclocking the CPU. Any suggestions would be appreciated. Thanks in advanced.

bobleblanc said:

The system is so fast and awesome that it refuses to shut down.

Click to expand...

Hi.

lol no.

There is probably a bios setting along the lines of "Power ON after shutdown" or similar to play with. Something along those lines. My old Intel motherboard even has it.

Disable WOL if still necessary, to test.

Check on - Resume by pci device pme

Thanks for the quick reply. I have been through the BIOS several times looking for such a switch. The new UEFI BIOS makes it a little easier. The only Power Settings I can find are on the " Advanced" menu in the APM section. "Restore AC Power Loss" is set to [Power Off] and "Power On by PCI-E/PCI" and "Power On By RTC" are both [Disabled] I will keep looking.