I have an ASUS P5W DH Deluxe with Antec 500W PS (modular plugs) 18 months old, Windows 7 and three SATA Drives.
I installed Windows 7 from scratch in December. Now, if I try to attach a third SATA drive, one of three things happens:
The computer boots normally, but the drive is not detected -- 35% of the time
The computer boots normally, and all three drives are detected and accessed - 5% of the time
The computer will not boot, not go through BIOS post and none of the fans or fans turn on all all. Note: The power light on the board is on. 60% of the time
I replaced all the SATA Cables and power cables with new ones -- but same problems exists. Generally, if I power down and wait an hour, it usually powers back up okay.
If I unhook the third drive, it will power up most of the time.
If I try another SATA drive, I get the same response.
The drives are good, because they will power up and show up occassionally.
I realize that there may be SATA drive issues, however, I have trouble shooted those for many hours and believe I have them set correctly....because they will work sometimes.
I don't think it is a component over-heating as when it does run, my monitors show the temperatures well within normal range.
I am looking for any trouble shooting hints, as it was up and running a hour ago -- though not recognizing my third drive, but I powered down and tried another drive and now it won't boot at all.
I agree, this really sounds like your PSU is failing. I advise you NOT try again until you have a known-good PSU to install. Running with a failing PSU does risk at least data corruption on your drives, and possibly damage to other hardware items.
A HD draws about 6 watts and I can't see it driving your system crazy. Unplugging your optical should give you back 20+ watts .... if you remove that does it help ?
I'd back up your system immediately to an external or whatever you have available.....then use OCCT to test your PSU .....look at the graphs at the end and see if you see any anomalies ....NOTE....OCCT can make a nearly broken PSU totally broken