I have been given acer 5100 and pressing power button it light momentarily and goes off. It will not boot anything, until I press power button and then hold down F9 or F10 keys then it will boot as usual and things goes well. I have even upgraded the bios to latest 3.1.3.
I'm running out of ideas and I thought I would ask. Since I'm not sure what the issue is then I though I would post here
I've read that some of that model have faulty hard drive connectors and won't work until the POST tests are bypassed.
I would try changing your boot order because you never know; maybe the bus connecting to the HDD takes a few extra moments to get on-line causing boot to normally fail, or maybe you can bypass some tests through the BIOS.