I have Asus striker II extreme motherboard and WD velociraptor 300gb.
They have been working together fine for the best part of a year.
Now, when I turn computer on, most of the time it will not pick the hard drive up and display "missing operating system" or "boot failure" message. 1 out of roughly 5 times it will boot fine and computer will operate with no problems.
I have tested the hard drive in another computer it works fine.
I have tried different SATA port and different power cable but no luck.
I have not performed any software or hardware installations recently.
I attempted to reinstall windows, however I came across the same problem where the hard drive was not recognised.