New
#11
It could also very possibly be an inconsistency in the power management between the OS and the drive (I'm leaning toward this), or an improper/missing driver that controls the power management (have the latest chipset/storage drivers?), or a faulty cable/connector, or.. the list can go on depending what info we get back after testing all these things. I wouldn't narrow it down to just those two things. Running drive tests is a good idea, but I would think there would be other disk corruption issues if it was actually failing.
Others have reported this problem happening with various drives. The PSU should have plenty of power to supply 3 hard drives, no dedicated gpu (his is onboard), and some optical drives even if it is crappy. If it had problems supplying power, I would think other drives would have the same issues of not being supplied power in order to be recognized by the system.
Just thinking out loud, though.
qreaigh - Is the "reconnect at logon" enabled for your network drive? That sounds like a completely separate issue.