Solved: 2019 Intel i7 MacBook Pro 16 throttling, overheating
My 2019 Intel i7 MacBook Pro was overheating and throttling on simple tasks. Monitoring a webcam, running the Music (nee iTunes) visualizer made the machine unusable. Here’s how I fixed it.
Processor temp wasn’t much above 60°C, but the fans were jacked, processors were all going nuts. Clearly CPU throttling was stealing cycles.
I found many reports online of trouble with the i9 build of this machine, but my machine had never suffered from overheating before the past few weeks. Maybe there was some serious damage to the motherboard. Or might I have to have the CPU re-pasted (heat-sink grease replaced)? I thought I might have to apply the killer fix for the i9: heat-sink pads on the VRM (voltage regulator module).
Resolved to the heat-sink pad approach, I ordered pad material, and also this really nice set of Marlin Screwdrivers from iFixit via Amazon. (That’s not a sponsored link – I don’t work for or promote those guys, but the screwdriver set looks and feels quality).
The REAL problem…
As it turned out, I only needed the P5 screwdriver from the set and nothing else. (It really is a very nice set – I like good tools). After watching videos that show how to get the back off the MBP 16-in without denting it I opened the back of the machine and was met with this:
The rest of the machine wasn’t any better – the thing was swimming in dust. Quickly I abandoned the idea of putting in heat-sink pads. I determined I’d clean out all the cooling pathways, then see if that made the machine run properly before I’d try any modifications.
Clean-up time:
With my dust-buster (with a brush end) and some canned air procured, I went to work. I had to pick a few chunks of dirt out by hand, but some just blew out easily. When I went to work on the fans, I was careful not to rev them too fast with the canned air. I blew both into the fans (in the circular area) and out (through the “comb” areas near the back of the machine. I vacuumed dust as I blew it out, and gently brushed areas with stubborn dirt.
When I couldn’t get any more dirt off the chassis and motherboard, I went to work on the inside of the removed lid with some tissue. I cleaned the surface well, but carefully, so as not to mess up anything there.
Once I was done, the fan looked like this:
And here are before- and after- shots of the entire machine.
The proof…
After reassembling the machine, running it hard all day with whatever I had available, the result: No throttling. None. Not. Any. Processor generally hung around 62°. Success, no re-pasting, no trip to service, no new machine – though this one works like it now. Very happy.
If you’re facing the same situation, I hope this information helps you out.
Remember: if you try opening your Mac, you may void the original or extended warranty. You could dent the lid (really!), cut yourself on sharp metal, or break the machine further. You could cause data loss and require further repair. There are a lot of reasons you might want to leave this to someone experienced. If you take it on yourself, please remember that I take no responsibility for any of the warranty trouble, damage, data loss, injury or anything else you might incur – that’s all on you, and I haven’t recommended that you follow any of these steps.