Standard x99m with a completely clearn windows 8.1 64 bit install, M2 SSD, several 3TB SATA GPT disks, UEFI/Windows Boot Manager. Standard "safe"
default settings and F3 BIOS. Nothing weird, all standard/ factory defaults, all clean stuff. Disks all tested on other machines, no errors anywhere.
If I restart the system with a USB external device plugged in, to the case front ports (off F_USB30_1 and F_USB20_2), then the BIOS goes into some weird boot loop and will not start. I see the BIOS logo multiple times, but it seems that my USB keyboard etc are dead - no caps lock light etc. So I deduce that I'm losing all USB functionality. Once this happens, the only fix is to remove the device, then manually clear the BIOS memory.
There are multiple badly documented settings around these USB ports. There are multiple reports of this kind of problem on the net, but no clear fix.
So what's the deal here, please. There must be some combination of the various settings here which will make this work. Why is the BIOS not starting, and does it write a log to say that somewhere? It looks like it's trying to boot from whatever USB device I plug in the front there - I didn't tell it to do that, so why's that happening?
Any help welcome. I guess I can RMA it and swap it for an Asus, although chances are they have their own issues...
Other thoughts:
- My mouse and keyboard are connected via a USB3 hub in my monitor, would they be better directly plugged into the USB2 headers on the board? Is there something weird about the USB 3 ports?