JonnyH
Member
That looks like one to maybe evaluate, but judging by the mounting holes for a fan and the metal top to the SoC suggesting good thermal contact for a heatsink, that might run a bit hot. But maybe the Pyra's current cooling solution is better than I think it will be, and we can afford to use a hotter chip, we'll have to wait and see.
Nearly all SoCs can be tuned for a specific power use (and heat output) - they just clock lower. No need to create a new SoC for each power target when you can just wind the same silicon down for the same result.
This same point should be kept in mind when considering any lower performance core due to power use or thermal limits - you really have to tune both for the same power output and compare performance then. While the omap5 is getting rather old now, being at least 2 major process nodes behind, a more modern "high power" A73 will likely beat the pants off an A55 (of a similar silicon node) in anything but the most limited scenario...
That is to say, if the A55 is having to turbo the pants off itself to keep up, it may use more power than a larger core in the middle of it's performance curve.
from here, it seems to run with lots of watts:
A lot of that will likely be i/o - PCIe signalling is /expensive/, if nothing is connected, or can be disconnected for large amounts of time, you should be able to completely disable the phy and save pretty much everything. Likely other busses can be disabled in similar ways (Assuming, of course, that the SoC implementation allows that - I would assume so, as it's just wasted power otherwise, and not really difficult to gate whole units in a coarse fashion like that..)
A usb HDD can draw "up to" 900milliamps @5v (so 4.5w) itself, so most of the difference may not be the usb implementation in the SoC itself.
And the rather high "standby" power use is likely a software issue - that's higher than many x86 laptops idle at - sceen on and everything....