[mdlug] Hardware Issue: Hard drive power requirements

[Raymond McLaughlin]

Michael Rudas (computer) wrote:
> Raymond McLaughlin wrote:
> 
>> I can't find any documentation stating what is considered a permissible current draw on
>> draw on an ATA hard disk. My guess is that it would be an IEEE standard or some
>> such, but I haven't been able to find any references.
> 
> Power consumption is not covered in the specs for IDE (hardware and 
> timing) or ATA (signals and protocols) on attached devices . The 
> specifications only extend to the 40-pin interface itself and whether 
> the cable is 40 wires (up to ATA33 speeds) or 80-wire (ATA66 and up).

Speaking of which. I sometimes see a boot message telling me I'm not
using an 80 wire cable when I know I am. Is the drive itself sending the
message? An IDE interface that didn't know the difference could cause
such a message, but wouldn't generate one.

> That having been said, if you can hook it up to a working system and run 
> some SMART tools on it (under either Linux or Windows) you can see what 
> the drive ITSELF reports about its self-monitor status. You will have to 
> turn on SMART in the BIOS on most PCs, but there are many free tools 
> available once you do.

Thanks Michael,
I did this last night. The drive checked out OK. Guess I'll have to be
even more strident in my agitation against cheap power supplies. It
still doesn't seem right that the list the power draw at 0.56 on the
label (and don't even call it nominal) when the peak is over 2.