Apologies if this is in the wrong forum, this is my first time here. If this post is too long, I can try and condense it. I usually leave PC in sleep mode, last night was no exception. I am used to it occasionally turning itself back on every few days (not sure why) so no surprise to see lights on my comp when I woke up. However, the screen was black with white text, with an error message something to the effect of the system being unable to locate the boot drive. Restart did nothing. I went into BIOS to swap my other internal HDD into boot drive but there's no Master Boot Record on it so the BIOS only saw my primary drive and DVD drive. I booted into Windows 7 DVD and tried to auto repair which didn't work after reboot. Trying to recover from system restore gave me an error. I attempted to do an in-place upgrade with Windows 7 to perhaps rebuild the MBR but it wouldn't let me use the upgrade option since I needed to be within Windows. Tried the custom install, it didn't even recognize my main HDD, it only saw my lesser 500GB WD drive and I wasn't about to choose to overwrite one of my partitions. I shut down the computer and went back to sleep perplexed. I woke up, turned on PC one last time (Was about to go out and buy a new HDD to install Windows 7 to so I could try and recover my missing HDD's files). Interestingly enough, the system asked me if I wanted to boot into safe mode because it was shut down improperly. Now it boots into Windows just fine with no problems. What's going on? Was told at electronic's store that it could be a fault SATA connector on my Mobo, meaning I'd need to replace the whole thing. Could it be the (4 month old) HDD? What else could it be? Why was the system fine after it had been off for awhile rather than through countless hard and soft reboots?