Try plugging the drive in again and see what happens. If it wont pass the Verifying DMI part, then try booting with the drive in each SATA port (try one port, if it doesn't pass, try the next port, etc), try different SATA data and power cables.
Once you've exhausted all options, won't hurt to go into the BIOS and make certain your SATA ports aren't setup for RAID when you're not using one, or any other oddity like that. If that checks out... likely the HDD holding up your rig meaning you need a new HDD. Good news about this is it's cheaper to fix and you can still rock your current rig. Bad news is, unless you feel like forking out tons of cash you just lost all your data.
Not too long ago my buddy's PSU went in one of his rigs, was a cheap PSU that came with one of his Apevia brand cases. It apparently took the HDD out with out. Put a known good and working OCZ GameXtreme PSU in his rig, connected everything and the unit wouldn't fire up. Disconnected all non-POST-critical components, rig fired up fine. Slowly started connecting devices one by one and it'd power up fine, untill I plugged his HDD in. Unit wouldn't even spin the fans with his HDD in. Not only did his PSU die, but it took his HDD with it. Never had an HDD prevent a rig from powering up so this was a first for me.
Anyhow, hope you get it sorted quickly and without being out too much money.
Keep us updated on your progress.