[alkonaut]

Word of caution 4K@27" is still pretty terrible in Windows. It's fine if you stay in specific apps for 99% of the time (such as a cad workstation or a Lightroom machine as in this case) but 27 requires scaling and many apps simply don't scale well.

The "simple" solution is to run 4K at 32" or larger where you can run att 100% scaling. Unfortunately, if you want a screen with decent color you are adding serious money to get to 4k@32".

[altano]

Why is this said in every discussion of high-dpi displays? I've been using high-dpi displays on Windows for longer than Retina was a thing and it's totally fine with only the extremely rare app/dialog not supporting it. My main display right now is 4k@27" with scaling on. Most apps are built properly and Windows now even supports fringe features like multi-monitor setups with different scaling ratios (a feature I was eagerly awaiting).

It's not perfect and I'll occasionally come across some old utility that was built 10 years ago and renders poorly, but never a commonly used or modern one. The level of inconvenience doesn't even register.

What do you want to use that doesn't work? Please be specific!

[alkonaut]

I definitely use lots of apps that aren't rebuilt in the last decade which is pretty common in the enterprise (in house stuff).

But among the "new" and "widely used" apps on my desktop right now that don't scale well (i.e. bitmap scale) are e.g. Skype, McAffee, Cisco AnyConnect (it seems about 50% of the apps on my desktop are not properly DPI aware, but simply bitmap scaling).

That's not the bad part though, I can learn to live with a few blurry bitmap scaling apps (and the odd miniature one that doesn't scale at all for some reason), but the bigger problem is apps that partially scale so they become unusable. Here is a screenshot I just took, of JetBrains DotTrace (a profiler) at 2x scaling (At a laptop with 15" @ 4K): http://prntscr.com/i4tpmb It not only looks terrible, but some things are actually unusable.

The bad thing about that kind of bug is that when an app is unusable, even if it's only one app of 100 that you use, you have no choice but to change scaling or resolution just to do that task which is a terrible interruption, especially for scaling that might require a logout to take effect.

Edit: I don't consider multi monitor with different DPI's a fringe feature, since the high DPI is very common on laptops so any setup with a laptop plus an external screen will often be using different scaling for the laptop screen and the external screen.

[altano]

Wow that screenshot of DotTrace is pretty bad, thanks for sharing. Skype supports high dpi just fine though (I use it regularly).

[mastax]

You may be able to fix this issue by overriding the DPI scaling for this application to System in its program properties dialog.

[wccrawford]

A co-worker is seriously considering switching back to Mac because so many apps are misbehaving in a mixed-DPI environment in Windows. Maybe if both your monitors are 4k you're okay, but it really sucks if 1 is 4k and the other isn't, such as when you have a laptop with an additional monitor.

[altano]

I actually use two monitors with different scaling and it works just fine for me. That’s why I mentioned it. What apps is your friend having trouble with?

[slantyyz]

>> Word of caution 4K@27" is still pretty terrible in Windows.

Well, YMMV. I have been running 2 x 4K@27 with 100% scaling for a couple of years now, and I am very happy. I don't adjust the default font sizes in my apps either.

FWIW, my screens are between 21" and 27" away from my eyes at their closest and furthest points.

[alkonaut]

Yes, I’d also opt for 100% and just ever so slightly too small text, over scaling.

You can always zoom text in web browsers, editors etc when so most reading is fine anyway.

If you have good vision and the screen not too far away it’s certainly doable - but 32 is a pretty big improvement.