I had the same problem with the same motherboard: it said press F2 for bios options or press F10 for boot menu, but the system was unresponsive to either key.
I turned it off and on a bunch of times to no avail, reset the cmos, and gave up. Then there was unplugging and replugging of the wires, followed by a successful boot. I suspect this may be a case of the power supply being insufficient to complete the bootup process, but I have little evidence with which to support a conclusion of causation. My advice is to avoid rebooting your computer unless you have no other choice once you get it to turn on.