2015 MacBook Pro 15" severe CPU throttling
My 15 inch 2015 MBP (2.5ghz i7, m370x, 512gb, OSX 10.11.4) is suffering severe CPU throttling while the discrete GPU is active.
Test 1: FCP X render from cold boot:
Test 2: FCP X render + Handbrake 4K → 1440p video encode from cold boot:
My laptop is suffering severe throttling, with typical CPU clocks in the 1-1.5ghz range. Curiously, though, CPU wattage and temperature are very low (15-20w and 70-75C respectively). The computer is in a well-ventilated area as well and fan speeds are at max (~6000rpm).
(For a point of comparison, here’s test 2 running on my 2015 27inch Retina iMac, with no throttling whatsoever:https://youtu.be/gQMabqB_-xA)
The laptop’s CPU doesn’t throttle when the discrete GPU is completely inactive (when the laptop is on integrated graphics). When the discrete GPU is active but idle, I still see some amount of throttling (CPU clocks in the 1.7-2.2ghz range):
I brought my laptop into a local Apple Store, and they ran a series of diagnostics on the laptop. They told me that the laptop passed all of their internal diagnostics and that I should treat the throttling as “expected behaviour” for the laptop.
I’ve never seen this kind of throttling with any Apple computer I’ve ever owned. What should I do from here?
MacBook Pro with Retina display, OS X El Capitan (10.11.4)
