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>you can use two 4k monitors at the same time -which is impossible with the M1 MacBook Pro

I have two 4K monitors hooked up to a 14" macbook pro currently. I believe it's the air that only connects to one external display.

According to the official documentation [1], the 13" M1 MacBook Pro also has this limitation:

  > If you're using a Mac with the M1 chip:
  > 
  > On iMac, Mac mini, MacBook Air, and 13-inch MacBook Pro, you can connect one external display using either of the Thunderbolt / USB 4 ports.

[1] - https://support.apple.com/en-afri/HT202351

Well, the 13” M1 MacBook Pro is basically the Air with a fan and more ports?

Yep, though that's really more of a question of chip: the M1 only supports two displays, for the laptop that includes the internal one (the Mini only supports two displays, and one only 4K via HDMI).

To be fair, several of my work laptops had a similar sentence in their user handbook, but two monitors were possible if you connected the wires before booting the laptop.

Really strange limitation, as it never scaled with bandwidth - so 4k 90+Hz was doable, but 2x 1080p60hz wasn't.

Some intel laptops (Ivybridge chips definitely, sandy Bridge probably) had such warnings because officially the chip couldn't support running three displays due lacking enough clock generators. Given the almost-analog nature of HDMI and naive LVDS, this meant trouble.

Thing is, Display Port has much more different physical layer derived from PCIE, and so connecting two displays by DP and running internal screen with LVDS worked just fine.

You could do 2x 4K displays with compression over a DisplayLink dock. Probably fine for UI stuff, maybe for video, not great for gaming.

The newer 14" and 16" models would drive them natively (or 2x 6K + 1x 4K with the higher end SoC) but then it's not much of a fair comparison by price. The single external display limit is only on the basic "M1" processor and not any of the Pro/Max/Ultra followups.

https://danielcompton.net/apple-m1-displaylink-multiple-disp...

The latency on DisplayLink drives me crazy. Completely unusable for me, unfortunately, it's become difficult to find docks which don't use DisplayLink :/

Have you tried it on m1? I'm running a 4k at 60hz and 3440x1440 at 75hz and they are fine - I don't think I notice any latency issues at all

Display link as far as I can tell is a weak video card on a usb connector. Does anyone else make something like that?

I used one with a white plastic MacBook to get 2 displays. I have a new on for my Linux notebook. It works well, but there is a little latency. For writing code/ web browsing it’s fine for me.

Displaylink and/or macOS does not support scaling on hidpi displays for some reason so it's not a good alternative :(

You have no issues with thermal throttling or inane power limits on Linux?

Which kernel version are you running?

Not that I have noticed. Currently running 5.17.3-arch1-1.

I don't usually push this machine too hard - maybe the most that I do is recompiling ffmpeg a few times a day, so it might just be a result of my usage patterns? I'll get back to you with more solid figures later tonight.

EDIT: Just had a play around with sysbench running a few prime number tests while compiling a kernel or two. The k10temp-pci-00c3 (CPU temperature under lm_sensors) seems to stick around at a crispy +64.1°C for a good few minutes, before rising to +65.6°C. It seems to drop back down to +64.2°C. The fan is pretty noisy. The CPU drops down to +50.0°C within 60 seconds of the sysbench benchmark stopping, and the fan noise is completely gone after 90 seconds. Temp is +36.9°C. Idle temp looks like it's around +34.4°C. Not sure how I can measure the db level of the fans? I do have a recorder, so I might be able to do it that way.

Not sure what a good way to actually benchmark the machine would be - it hasn't really come up as a necessity. Maybe I can use the Phoronix Test Suite?

EDIT 2: Doing some searching, maybe I got the machine just in time? 5.17 looks like it added some code specifically around P-states for Linux. https://kernelnewbies.org/Linux_5.17#New_P-State_driver_for_... ... Someone else with my exact same kernel version reports AMD issues being fixed in Arch that they previously had. https://www.reddit.com/r/archlinux/comments/u7kwza/recent_ar...

Regarding the edit, that would make sense. I have the same laptop and first tried to run Ubuntu LTS, had some problems with the thermals, even though it was definitely usable.

Tried Arch (with the 5.17 kernel, from Ubuntu LTS's 5.4 kernel) and the thermals were more or less identical to Windows, including the fan behavior.

It's a really nice little machine! :D

> maybe the most that I do is recompiling ffmpeg a few times a day, so it might just be a result of my usage patterns?

Maybe. If you compile in short bursts it's probably not going to affect you as much. With 4K screens and compiling a tiny bit of Rust, it starts being noticeable rather quick.

I did notice that newer kernel versions do behave a bit better, but still require a bit of help to keep consistent performance plugged in.

From June last year until February this year, I was running the stock Kubuntu 20.04 kernel on a ThinkPad T14 with no thermal throttling or power limits. I would often have a few Docker containers running, a JetBrains editor (Java, shudder), Firefox with some addons and well over 100 open tabs, Chrome with the devtools open, MS Teams, Thunderbird, and some smaller apps such as Keepass, Telegram, Anki, a dozen terminals, and Emacs running. Never had a problem with memory (I think only 8 GiB, actually) or CPU (I don't even remember which Intel CPU it had). It was also connected to a docking station with two external monitors and an external keyboard.

It was the smoothest Laptop I've ever used with Linux, which I've been doing since 2008. Everything worked out of the box, including external displays, wifi, printing. I'm sure that a major portion of that experience was using a Kubuntu LTS release.

> RAM (I think only 8 GiB, actually) or CPU (I don't even remember which Intel CPU it had

Sounds like you had one of the cheaper T14's, it's likely you didn't run into any power limits due to that. 1080p screen as well, I presume?

Kubuntu 20.04 and its kernel version certainly throttle power on the higher-end T14's I've seen. If that's lifted then they throttle thermally, unless you manually force both cooling and power limits higher. Windows handles it all tad better, but the battery life is nothing to be amazed of.

I do believe that is was a 1080 screen. I almost never used it without an auxiliary monitor (mostly two aux monitors), I would have been just as happy with a desktop. Alas, the company only provided laptops.

These issues were caused by buggy intel software back in T460-T480 era - lenovo considered the problem big enough to consider not using Intel thermal management code in future designs

ok so how is the battery life though?

Not amazing, not bad. Probably around 5-6 hours using intellij and Chrome.

Not surprised your ThinkBook is beating the M1 MacBook since you crippled the Mac with 8GB of RAM.

A 'Pro' device shouldn't be sold with crippled specs.

Macbook Air has never been marketed/sold as a 'Pro' device. There is the Macbook Pro line for that.

I am comparing this to a MacBook Pro. Edit: Admittedly the 8GB 2020 model, but still.

I also thought you were talking about the Air and had made a mistake when you said “pro”. I just totally forgot about that model until you doubled down.

That's absolutely true. I'd say it's a marketing failure on Apple's part.

I don't want to sound too snarky, but I don't think you got the point of my post.

I love the M1, it's a great work machine, I have very few complaints about it. I hardly ever hit 100% memory usage, and if I do - it's thanks to either Chrome/Spotify/Teams/Slack/Discord.

I think - and this might be a bit controversial - the ThinkBook is better... because it is. The M1 is a great chip, awesome thermals (no fan!), but the laptop booted into Windows is faster.

Hey, maybe it's the memory, who knows! It doesn't swap, so I don't think it is.

You can read my parent post for my reasons. You can't quite run Windows or a stable Linux on a MacBook now, can you? Can't quite remove a 4GB stick and replace it with a 32GB stick, right?

To each their own. I'd have spec'ed that MacBook Pro out to 16GB though. I don't do Windows and I have on-prem cloud VMs (config'd for 32GB) for Linux. I don't need a Linux desktop (shudder!) either. I'm sure your THinkBook is great, but I prefer the Apple ecosystem and the "shit just works" of my Mac (although I'm still on an i9).

100% my flow too after a lot of experimentation. I have had several clunker lenovo machines and have run linux as a daily driver on and off for several years (I always wanted it to work, it was just infuriating with random glitches and the verbosity required to get a sane setup stable).

M1 MacBooks are legit, the Pro is the best machine I have ever owned by a long shot (several X1's, T Series etc) the screens are beautiful and I can get on and do whatever I need without worrying about glitches. I run commodity cloud linux VM's on things I need to deploy/monitor, its FAR easier (imo) to write the software on my Mac and then move it out.