Random ability to boot from usb on Biostar TF720 A2+

[glave]

Is there anyone else that may be using this motherboard? I seem to get random results on my ability to boot from usb on it. The first time, it worked great, then following, I get a message to select proper boot media or restart. I've tried 3 different usb keys, sony, sandisk cruzer, and a pny. Same random results. It seems that each key worked great the first boot only, and after that, they usually did not.

[SSD]

Some MBs/BIOSes have difficulty remembering the boot settings as the drive assignments seem to become almost random.  Go into the BIOS and see if you need to reassign the USB boot device.

[glave]

It's keeping the settings between boots. I can actually see the usb device listed during post as it lists the hard drives as well. Its as if the usb key is suddenly no longer bootable, but I can still get it to boot on occasion after random cold boots.

[RobJ]

If different flash drives can boot occasionally, then they are probably fine and the BIOS settings are fine, so that would implicate the USB ports themselves.  Try different USB connectors, and if necessary, those connected very differently such as ones on the front of the case.

 

Here's a wild shot, probably ridiculous, but since you say that each drive consistently boots correctly the first time after preparation, and then its behavior is different, less trustworthy, that sounds like some kind of self-modifying action going on.  You might test them for some sort of Conficker-related corruption, also the machine you are preparing them on.  Try preparing a fresh untouched drive on a different machine guaranteed to be clean.  I know, sounds absurd ...

[glave]

I'm wondering if anything else could be at work. I've tried all suggestions so far, and still no luck.

 

I just created 2 bootable cds, one using plop, and the other using the panasonic boot disc mentioned in the old hardware thread. Both cds boot fine, they see the flash drive, but when they tell it to boot, I get 'Remove discs or other media. Press any key to restart'.  I get this message quiet often when trying to boot directly from the usb drive also.

 

I've tried different usb ports, 3 5 different usb drives, created the drives from an absolute clean install of windows, but I'm still getting random ability to boot. There is no one perfect way I can get a reliable boot (from cold boot or not).