[reitzensteinm]

I had Windows and Mac laptops back then, and the HN snobbishness around the superiority of the Mac was genuinely baffling.

My i9 2019 MBP with discrete graphics was probably the worst laptop purchase I ever made. Docking it to an external monitor would enable the GPU, so even when idling it would run the fans and drain the battery.

I’d read cautionary tales about Windows laptops being pulled out of backpacks scorching hot as they failed to shut down. But that happened to my Mac all the time, too.

The M series though is incredible. I can’t imagine buying a Windows laptop now.

[pja]

The i9 was notorious. Would thermally throttle almost instantly & for any sizeable build job would end up slower than the i7 IIRC.

Intel really made themselves unpopular with Apple during that period.

[aeyes]

> Intel really made themselves unpopular with Apple during that period.

You can't tell me that this wasn't known by Apple before shipping the product. Why did they not provide adequate cooling for the CPU?

[pja]

This was a laptop, so cooling was very constrained. The fans can only be so big & you can only shift so much air in & out of a MacBook.

I presume Apple knew perfectly well but wanted the halo product to sell to those people who will always pay extra for the perceived “top of the line” product. Once Intel branding had created an i9 that was a bigger number than an i7, then Apple was going to sell it.

It was faster than the i7 after all: just not for very long!

My entirely speculative theory is that the poor thermal characteristics of that era of Intel CPUs didn’t really become apparent until quite late in the development process & by that point Apple had probably committed to buying a fair chunk of Intel’s output.

[close04]

> Intel really made themselves unpopular with Apple during that period.

Intel just reenacted IBM's history with Apple, particularly the G5 era. That CPU was instantly a no-go for anything mobile. In workstations it was cranked ever higher with very poor power-frequency scaling, needing water cooling for the beastly 200W idle power consumption and close to 1kW full throttle.

That went well so was a perfect role model for Intel's i9.

[smarks]

Oh yeah, I forgot about the graphics.

I had (and still have) a 4k external monitor. Naturally I wanted the MBP to drive the monitor with a resolution that took advantage of all the pixels. Unfortunately with most monitor settings the GPU power consumption would produce enough heat to run the fans even if the rest of the system was completely idle! If I set the output to full HD the GPU would cool down and the fans would turn off. But full HD on a 4k monitor is a waste.

It was very strange. I could drive the monitor at 4k but with the image upside down, and the power consumption would be low. But flip the image right side up and it would run hot and turn on the fans.

It took a couple weeks of fiddling, but I finally found a combination of refresh rate, resolution, image orientation (right side up!), and cabling that let me drive the monitor at high resolution without running the fans. What a pain.

(I used iStat menus to monitor GPU power consumption. At “good” settings it consumed about 5w. At “bad” settings it would consume 17w. At a bad setting you could immediately see the various temperatures go up and the fans spinning up to compensate.)

[lobf]

How could orientation and cabling affect heat??

[smarks]

I don't know, but I did observe differences in power consumption caused by all sorts of unexpected things.

At some point during all my fiddling with this stuff, I discovered a correlation between GPU power consumption (as indicated by iStat Menus) and fan speed. For example, if I switched to high resolution, the power would increase, and at low resolution, power would decrease. And of course more power means more heat, which causes the fans to run. That kind of made sense: moving more pixels consumes more power.

But I also observed an effect caused by refresh rate. Oddly, I seem to recall 30Hz would cause increased power draw but 60Hz the power draw was reduced. Yes, this seems counterintuitive. Since I didn't have a good model for what caused the increased power draw, I decided to try all combinations of the settings. On a lark I tried inverting the image and it actually affected the power draw! Probably has something to do with the access order of memory, but I don't really know. And indeed it seems odd that running the image upside down actually pulled less power than right side up.

The cabling issue was a bit more complicated. My initial configuration was to run the video through a dock, with the dock's video output going to the monitor. That always resulted in high power draw. Connecting the computer directly to the monitor did have the effect of reducing power draw... but only in certain configurations.

[jaen]

Changing orientation affects which parts of the display processor are used. In general, the low power states on GPUs are very capricious.

eg. from personal experience, on older Nvidia cards (1080 Ti), just adding +1Hz to the refresh rate (or using a slightly higher resolution, or 10-bit color, or no DSC etc. etc.) caused it to never enter low power mode, changing power consumption permanently from 10W -> 50W.

AMD GPUs on even the most modern Linux kernels don't enter low power states properly. If you do change the power profile to do it more often, browsers become a laggy mess.

[carlosjobim]

Apple hardware quality on the laptops was bottom tier during the 2016-2019 "butterfly" era. There's no denying.

[mfro]

It was a truly ridiculous idea to put an i9 in any laptop. That generation of i9 is difficult to cool even with liquid cooler systems in big ATX cases.

[volkl48]

Just to remind, the mobile + desktop lines are not the same thing even if they both get the same branding.

The top end chip in the 2019 MBP was the i9-9980HK, which had a TDP of 45W.

Would have been reasonable in a chunkier workstation/gaming type of laptop with the kinds of cooling solutions those usually get, it's not something that needed an actual desktop liquid cooling solution to run well.

But obviously the 2019 MBP design/cooling was not up to that task.