I doubt the psu would corrupt the HDD, but it might be possible... could be when your optical is being read with your hdd writing that might just barely strain the psu... because I can't see your system using that much power anyways...
You could always try a new 200W PSU or so... a HDD only takes 10W or so max, so your probably right on the edge. Go to a local comp store, buy a psu, and give it a shot. If it still has problems... then you have the little fail-safe called a return 😀