MacOS in particular does an excellent job of rendering 2560x1440 to a 4K screen, and the increased DPI over a regular 1440p 27" screen is very noticeable.
Another option if you're not a fan of 27" displays is a pair of 24/25" 4k screens which can be run at a scaled 2304x1296 resolution. This still provides a decent amount of space without text being too tiny. Alas, 4k monitors <27" are increasingly rare these days.
MacOS in particular gets amazingly slow when you don't use a 1:1 or 2:1 scaling. I too have have two 27" 4k screens and they made the machine unbearably slow. It got so bad that I now treat them as 1440p screens and let the screens do the scaling. It's not pretty and slightly hazy, but at least the machine is usable.
Also sometimes the virtual memory subsystem seems to get confused or overcommitted (e.g. after running a bunch of large VMs in VMware) and from that point on everything is just slow, even if you shut down every VM to relieve the memory pressure. It may be related to macOS's use of memory compression.
Then there are various background daemons (mdworker, syspolicyd, photoanalysisd, etc.) that occasionally wake up and decide to eat all of your CPU while simultaneously hammering your file system. The only effective response, short of disabling the offending service (which is much harder than it is on Windows or Linux, due to SIP) seems to be to let them run their course as they decide to scan every file they can find for the 100th time.
And when your laptop heats up, then macOS starts throttling the system via kernel_task processes that appear to be using all of your CPU.
My work laptop is a 2019 i7 MBP, it struggles with my 4k monitor regardless of scaling. I bought the cheapest mac mini last year to see what the M1 fuss was about, and it has no problem with the 4k screen, even with scaling.
Other OS's? Windows is passable until you start transitioning in and out of full screen. Linux...
If there is a speed decrease, I can’t notice it on an M1.
I’ve seen a lot of people parrot this claim or claim it renders awfully but have yet to experience any evidence. On the contrary, it’s been glorious.
Edit: if you do 1440p scaling on a 4K on macOS make damned sure you select “1440p (Hi-DPI)” other you get a pixelated mess.
I don't "parrot" the claim. I've experienced the problem. It's day and night. After installing Monterey I couldn't run MS Teams on the external monitors anymore. It more or less locked up and I couldn't move the window back to the laptop screen. This was repeatable.
The whole problem went away when I selected 1440p (the "low resolution" one). It's fugly, but at least I can actually use my other monitors.
I spent months trying everything I could think of: downgrading to Catalina, turning off transparency/shadows, running as few background services as possible, and not using scaling at all (which was the most effective solution). And this was only with 2x 4K monitors; I added a 3rd more recently.
Nothing worked. Thermal throttling and insufficient sustained power were two problems I was able to identify (the 96W adapter is not sufficient for the system's peak power load, so it uses the battery to get over 96W of draw).
Eventually, I broke down and bought an eGPU (Blackmagic eGPU) which solved the problem. For about ~$700, I'm now able to use my machine without a hiccup. Not a great or affordable solution, but it has made my $3,100 machine usable again.
I’m pretty sure my i9 model has the lower end 5300M.
Another question: what are you using to connect the monitor to your laptop? USB-C to DisplayPort, here. I formerly used HDMI off of a USB-C hub but it was a bummer.
It’s pretty bad the Apple still denies any issue, not being able to use an external monitor at all through covid suuuuucked
32” at 4k (native res, 1:1)
30” 2560-by-1600 (native res, 1:1) ( few monitors support this physically, but two are my goto: old 30” apple studio displays , and a 30” old dell monitor. Both can be found on eBay at very low cost , but do use 2 to 4x the power draw as modern monitors)
I always try to get the company to pay for me of course, but I have no patience for suboptimal equipment any more, so I’ll buy it myself if I have to.
I may try pushing for a monitor refresh again once we go back to the office.
An option that I think might be interesting is 3 displays side by side, but with the center display in portrait mode rather than landscape mode giving overall an inverted T shape to your combined display space.
I find this works well for the "adjustable height desk" systems one puts on top of a regular desk. They usually aren't wide enough to have two monitors with one directly in front of the user. The portrait monitor, if the cables are long enough, stays on the fixed-height desk.
I'm unable to use two monitors side-by-side anymore. Working for hours with my head always turned to one side gives me headaches.
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Edited to add note on desk-placed "adjustable height" systems.
How does this work? Will it just upscale or is e.g. text still rendered at 4K? Rendering not at native resolution results always in blurred edges in my experience.
Here's an album with a pair of screenshots from my own 4k display: https://imgur.com/a/7AHZZZv -- the scaled one is how I normally use it.
The Windows UI scaling slider behaves in exactly the same way, though fewer apps include 2x or 3x bitmap resources.
This makes it sound as if macOS upscales a 4K render when displaying to (for example) 5K monitors, but on a 5K monitor everything is ultimately rendered at a full physical resolution of 5120x2880. But in the Displays Preference Pane, the logical resolution is set by default to 2560x1440 (2:1). One can choose a logical resolution of 5120x2880 (1:1), but I can't imagine anyone working like that.
Whatever-sized display viewports are just crop windows into it, and the crop window in internal canvas terms is scaled as necessary, and then it renders the vector canvas onto the raster viewport.
"Panel Lotto" (as I know it at least) refers to the company's policy regarding returning a panel that had dead pixels on arrival. Some policies don't allow customers to return those displays even if it has a dead pixel, as it wouldn't count as a defect. That's why it's a "lotto", it's pure chance if you'll receive a perfect display or not, and if you do you have no recourse.
I'm not sure how it works out in practice, I've never received any display with dead-pixels on arrival.
To a lesser degree the "lotto" idea happens with CPUs too in terms of overclockability potential. Certain serial numbers performed better, it became a lotto unless you went out of your way to purchase specific ones. This feels a lot less wrong than the panel lotto aspect tho.
You are right in that it feels criminal, it's not even the same product.
Like the Nintendo 3DS back than? Where you couldn't figure out, which screen(s) you would get pre-purchasing or Lenovo with their display panel and keyboard lotto?
I have the slightly better version of this. The only major difference is the stand AFAIK - but if you have multiple monitors you might as well get a good VESA mount to arrange them while keeping your desk clear.
Power Toys?
People keep saying this but I don't.. see.. it. Everything scales great on my setup. I could make one letter cover the entire screen if I wanted to - the DPI is not really relevant in that sense. You still have to set size up to your liking. And I do not have great eyesight (contacts/glasses).
Admittedly, DPI does play a part when you have multiple monitors with different resolutions. I have solved that by wrapping my launcher with a script that detects the screen, reads the DPI and scales accordingly. Which, to be fair, is not something you should expect people to do :p
My desktop uses an LG-27GL850 and an LG-27GN950. One is 1440p, the other is 4k. Both are 144hz. I first bought the 1440p, which is great, then I bought the 4k one. I wanted to keep the 1440p one for gaming, but as it turns out, I don't game, so I regret not getting two 4ks.
I did extensive research before getting these, and after a year with them side by side, I can for sure see the difference when I read text. The fonts (and everything) just pop more.
I would be completely fine with 1440p, that looks great as well, but since I am at my computer for the better part of my life, a few extra dollars was (and still is) worth it for me.
PS: 144hz was almost weird at first - the cursor and scrolling is so instant. Highly recommended.
It will probably be obscenely overpriced, but I'll probably get a few for work for people who don't like their curved ultrawides.
The 39" 4K I've been using since 2014 has spent many a year in pillarbox attempting to preserve my neck and eyes, but it's still ultimately too large. I'd love to replace it with some smaller high res non-widescreen panels.
I wrote up a very big monitor selection guide at https://nickjanetakis.com/blog/how-to-pick-a-good-monitor-fo..., I try to keep it up to date by supplying alternatives to the ones I've purchased. Some of the monitors I recommended were $330 when I bought them but are now $500-700, although sometimes they come back in stock at $350ish.
I made the switch around 5-6 years ago and still think it was one of the biggest upgrades for general quality of life improvements when using a computer.
The only reason I haven't gone 4k is because using one at 100% scaling at 27" or less isn't really feasible due to how small the text is and using a 36" one to be able to comfortably view it at 100% scaling feels too big for using it in a normal desk environment. Personally I'd rather have the flexibility of 2x 24-25" 2560x1440 monitors, plus 120hz / 144hz 2560x1440 monitors are very abundant if you're into games (although you can make a strong case that 120hz+ is very noticeable and useful for general usage too).