Both grounds needed to power on a HDD?

[Sniper82]

Ok I unplugged my power from the PSU whiles messing with it. Anyway I didn't pull the plug away from the HDD good and the 5v was hanging on one of the ground pins on the HDD. Don't ask me. I should have moved it away good but wasn't thinking or paying attention.

Anyway when I went turn on the computer little smoke came up out from under the HDD. I turned the PC off immediately. Well I went ahead and plugged the power back into the HDD and it works fine. After testing it I shut the PC down to look at the HDD to see the damage it done. It burnt some of the trace on one of the ground pins but didn't lift a trace. But I noticed both grounds lead to the same spot on the HDD.

Curious as long as one of the grounds are find will the HDD still function no problem? Even on down the road?

 

[Zepper]

Usually yes. All grounds are common in today's ATX systems. It wasn't necessarily so in the old days and that 4-pin drive connector is just a holdover from then. Be more careful. You could have blown out your PSU as well as your drive...
.bh.

 

[Sniper82]

Think it will be ok though? If the HDD decides to quit working would it just not power up?

 

[Zepper]

It should work fine and yes, if the ground plane floats free, the drive won't spin up. But there is an alternate path to ground thru the drive's metal frame as long as it is in contact with the case metal.
.bh.

 

[Sniper82]

k thx man

 

[amaiman]

It would probably still be a good idea to backup your data, though...

 

[Jeff7181]

Actually I don't think the ground wires are common... if they were, there wouldn't be two. I believe one is for the +5 volt and the other for the +12 volt.
The reason I believe this is because when I was testing the voltages of mine with a DMM, if you hook the DMM leads up to the wrong ground wire for the voltage rail you're testing, you don't get the correct measurement. So... it would seem as though one is the -5 volt wire, and the other is the -12 volt wire.

 

[Zepper]

Both ground wires go to a common point inside the PSU and inside the drive. If you got different values then there is some other problem. There hasn't been floating grounds in PSUs since the days of analog PSUs.
.bh.

 

[lenjack]

The ground wires are identical. I agree if you got different readings, there is another problem.