At three years old the seagate is close to end of warranty for sure.
I suggest you get a new hard drive and using drivexml, clone everything to the new hard drive.
Leave the old one alone after you unplug it [but do not remove it from your computer] an keep it as a back up of sorts.
Now using only the new hard drive, see if you get any BSOD's. If you do then it is not bad sectors etc.
Secondly. This will also make sure you have a back up of everything [the old drive] so that NOTHING is losr while you fiddle with things on the new drive.
If everything goes south can you afford to lose all your info on your hard drive?
I didn't think so.
Also a new hard drive is a small price to pay for peace of mind.
I hope this helps