"DS" writes:

I have a 12 volt power supply that converts 110AC to 12V DC (actually 13.5.)
I haven't used it for some time.
I was using it to check some wiring and find it is now putting out 21 VDC.
???

As someone else noted, check it under load. But if it is the typical
Radio Shack or similar "12 V" power supply, then it probably is a regulator
problem, possibly just bad solder connections or a shorted transistor (though
that wouldn't happen from sitting around).

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(Michael Black) wrote:

...
And ironically, you might find that the smaller the capacity the
more the platters.

That might be interesting trivia if it were true.

http://westerndigital.com/en/product...asp?DriveID=85

Click on the Configuration tab for each of the sizes and look at a
number of platters.

If you can find data for a series which supports your contention,
please post the link.

But technology is changing so fast that indeed, a drive that appears
similar on the outside may have a different bit density on the platters.