Roger Hayter wrote:
If I get one of those semi open frame type SMPSU's I could put it
inside the PSU case as that only contains the one 120mm fan atm.

That's a *lot* of power for a fanless Atom based board. My full-blown
desktop machine with a (6th gen, or maybe even 5th gen) I5 and three
disk drives only consumes 18 watts when idle and maybe 25/30 watts
when working hard. That's a maximum of around 3 amps at 12 volts.

I doubt very much if you need anything like 7 amps.

A significant component is the starting current for the drives. If
this is not specified then you really need an oscilloscope to check.
Even laptop drives may draw twice their rated current when operating.

So stagger the startup. Most PSUs will handle short term surges more
than their rated output anyway and/or the output will droop a bit as
the drives spin up.

--
Chris Green
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