Can anyone give me any advice to fix this? I have no software installed (not even an OS) and when I turn my power on all my fans and LEDs turn on, then just stop. I have no idea why and can anyone help?
Whose motherboard is it. I had a similar experience with an Intel motherboard, DQ45CB. Never did find a good fix. Didn't seem to effect the computer it would turn back on and off after a shutdown and when you turned power on to the board, ie. plugging in or flipping on the PSU switch, it would power on and off but other then that the system ran quite stable and reliable.
Did you check the CPU itself or the heatsink fan/thermal paste? If you can get to the BIOS before shutdown check the temp sensors. I once installed a cpu heatsink fan a little off-kilter and it led to a similar issue.