On 04/11/2010 10:34, Tim Small wrote:
On 04/11/10 01:54, John Robinson wrote:
operating power is 7W, the maximum transition power (whatever that is)
is 40W - yes, 40W
I'd guess this is either during spin-up, (or spin speed change if
enabled), or possibly even the "inrush" current when power is first
applied to the device (i.e. only for a few milliseconds when the machine
is turned on), and so probably wouldn't cause much of a problem unless.
Yes, reading the spec more closely indicates that this transition power
is the drive waking up from its lowest power-saving mode, so it's
spinning up the discs, so that's not going to be happening much.
In second place after spin-up events, from the same spec, we have peak
power during random reads of 24W, and 26W for writes, still more than 3
times the average operating power. I take "random reads" to mean lots of
seeks, so as Bill said, heavy seeking could be rather rough on a PSU.
Cheers,
John.
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