I'm not sure if this is the right place to post this. It seemed like the closest fit in the SX sites, and this meta post seemed to suggest it was the right place. Here goes!
My computer has recently decided not to boot from my hard drives, though it seems to recognise both of them. After the BIOS loads, it shows me this:
I'm certain the drives still work, since I can occasionally boot after changing all the cables around - but then I come back the next day and the same configuration fails to boot.
I wanted to take the chance to ask: how does a motherboard usually determine where to boot from? In this case, it looks like the motherboard found both hard drives, but just ignored the fact that the 60GB drive has Windows on. Or are there other factors that might prevent the drive from being bootable, even if it is 'working'?
EDIT: Of course, I should mention. Motherboard is a GA-MA790XT-UD4P, the hard drives are a 1TB Samsung and a 60GB Intel 330 series SSD.