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Comment by oaf357 | Hacker News Reader

Only 10W for all that? While I'm a little sceptical that is an impressive number.

Yeah but - 10W all getting radiated inside a single 12x12mm BGA package? Isn't that a lot? It sounds to me like that'd be running very hot...

I had a project with a Raspberry Pi2 which was only drawing ~2.5W all up (including the wifi dongle), and it got flaky when the sun shone on the case and got it a bit warm.

10W is probably on the high-end for passive cooling of such a package, but zero problem with a fan.

For reference: an Intel Atom (e.g. Braswell) CPU has a TDP of 6W and a pretty large passive heatsink.

also for reference ~10W is Pentium ~100MHz territory. Afair 133MHz was the first one that required fan on top of the heatsink.

Fwiw my 486dx2-66 had a fan, and when that fan died we noticed because of corrupted memory crashing the system. Compared to modern CPU coolers it was downright tiny, but required.

From memory though, they were closer to 20mm or 30mm square though, right? (At least the outside package which I'm assuming is what the 12x12mm spec is referring to)

DSPs have insanely tiny power per peak OPS. The problem is that they are not good at running general purpose loads.

Lots of small cores is a significantly more power efficient model than one big core. Picochip, for instance, managed to spectacular things on a low power budget, but you needed to really think out you model and how you were going to apportion work to cores.

They should thank Cadence for the IP cores I guess.

On a similar note, an RPi model B consumes ~5W, which is damn good for a full-fledged computer.

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