Intermittent issue booting, windows 7, unsure of problem

Hey there all,

Been having a somewhat intermittent problem with my home built pc here.

The issue: My first concern came when my computer would auto-reboot when i manually went into start menu and selected shut down (absolutely positive i clicked the right option). The pc acted as if i hit restart and simply came right back on, shutting the pc down again did not incur the issue, this happens uncommonly, but enough to recognize it.

The big problem: after shutting down the computer (this is the second time this has happened) and coming home some hours later from work to get my game on I would boot the computer and be greeted by an unresponsive set of monitors. I can try rebooting all I want, the monitors are unresponsive but with no curious OS beeps. I solved this issue last time by unplugging the sata cable from my HDD and plugging it back in, which allowed the computer to come on peachy keen.

Today it happened again, same resolution.

My question about this is that...i'm using a dual drive system, i have an 80 gig SSD which has my windows partition on it and is my boot drive, the HDD is for storage, if that's the case then why would unplugging the HDD resolve the issue, why wouldn't it be from the SSD side?

Could this be caused by a virus? I'm extremely careful with what I do, I know enough to build a pc, troubleshoot it for the most part, but i'm not an expect. Any information would be useful, I do have the extra warranty on my MOBO from TD and the rig isn't even a year old.

Thanks for reading!