Is there any solution??

Hi guys!

I just turned on my Comp and as simply as this: It doesn´t boot up with my primary HD plugged in, it´s a Seagate 500GB 7200RPM. I tried it on this rig and still the same, at least in this one shows BIOS screen but it won´t go further either.

Yesterday, light was gone like for 5 seconds, of course it turned off my Comp even though I have a small UPS, but I´ve waited like 30min and turned on, and everything was normal.

Have this ever happened to you??...Is there any solution, at least to recover data??

Hardware:
- My own: Phenom II940, gigabyte 790x-ud4p
- Where I´m writing from: C2D e6600, intel 965SS

Thanks in advance guys.
Regards!!