Windows 8.1 scaling discussion and questions

[Neon01]

I'm in the process of adding an Acer 28" UHD display to add to my current LG 34" 3440x1440 21:9. The vertical dimension of these displays is very similar, but clearly they have pretty vastly different PPI specs. I've been doing research on the web about windows scaling and how to apply it differentially to various monitors. From what I've read, this is either broken in Windows 8.1 or doesn't work in a way that's predictable.

It seems that Windows 8.1 automatically applies scaling based on the detected resolution of your display, and the scaling slider only changes what that "base" scaling is. Is this true? Can anyone speak to how to get this to work if I want a (relatively) constant desktop UI size across displays?

Also, I see a lot of confusion regarding how scaling applies to applications. I initially assumed it simply wouldn't apply to any applications that are run in fullscreen mode, and would only work for the desktop. I don't believe this is true. Can anyone confirm that one way or another?

If Windows is applying scaling in fullscreen apps (primarily talking about games here), what does that mean for the game's rendered and output resolution? Games that support UHD native res would be fine, of course, but what about games that only support resolutions well below that? Before I needed to use Windows scaling, I trusted my GPU to do the scaling properly when it was necessary. I'd assume that a GPU (hardware) would do a better job of scaling than Windows (software) for an older fullscreen app that didn't support UHD. I don't really want Windows monkeying with scaling in my apps, but does that mean that I'm going to have to manually turn it off every time I launch a game if I want it on for my desktop?

Any other thoughts or discussion are welcome. It seems like this would be something that would concern many enthusiasts with the wide range of monitor resolution and sizes nowadays.

Edit: found this discussion on a windows blog by MS: http://blogs.windows.com/bloggingwindows/2013/07/15/windows-8-1-dpi-scaling-enhancements/

It sounds like Windows indeed auto scales based on the resolutions of the monitors it outputs to. Unfortunately this is a really shoddy way to implement scaling, and the article doesn't talk about how or if you can fine tune it by display. About halfway down the page they show three different displays with vastly different DPI, and show "before and after" shots of scaling is applied using the basic calculator app. The scaling brings the highest DPI UHD display nearly into parity with the super low DPI display, but makes the middle one huge. It's probably at least 25% larger than the others. With no way to tweak this, the system is pretty much broken, as it could break more than it fixes. Ugh.

 

[XoR]

you can enter custom DPI without any problem
as for games (mostly older games) you can disable scaling in exe file preferences if it's not working right

and there is no such thing as 'windows use software scaling' as it uses hardware scaling too.

 

[Neon01]

you can enter custom DPI without any problem
as for games (mostly older games) you can disable scaling in exe file preferences if it's not working right

and there is no such thing as 'windows use software scaling' as it uses hardware scaling too.

You can alter DPI just fine, for a single display. You can't adjust different displays separately. Good tip on disabling scaling by app, thanks.

By hardware I mean using the GPU hardware. Windows doesn't process anything in hardware, since it's purely software. Same idea as hardware/software vertex processing. Orders of magnitude faster and better with hardware.

 

[General Lee]

A single 28" 4K display works ok with the current Windows scaling, but it does have issues with third party apps either going fuzzy or not scaled and too small. When you add to that other displays with different PPI things get problematic. Screens are either too large, small or the text is fuzzy. There is no working fix for it. I've tested this with a setup that had 28" 4K, 27" 1440p and 27" 1080p monitors. I could get the scaling decent on 4K and browser but text would show up fuzzy on the 1440p and 1080p monitors, and some apps on the 4K were bad too. The other option was to have no scaling at all, but that meant the 4K display was far too tiny to use. After the tests my personal opinion is that unless you go 40" 4K with no scaling, I don't think 4K is worth it for desktop use with the current Windows scaling. It can work for video and gaming of course, but given how new games barely run 1080p at 60 fps I think there are better options for gaming.