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How to - external monitor and scaling


I'm trying to figure out how best to configure scaling to work with an external monitor(s).

Right now, I have my Surface Book connected to the Surface Dock. When docked, I am using an external monitor with a resolution of 2560 x 1080. Display is set to ONLY use the external monitor. When I go from docked to undocked, the scaling is just a mess. I have to sign out and back in.

Is there a better way? Isn't there a way, for example, to set the laptop display to use 200% scaling and the external monitor to use 100% scaling?

Thanks in advance for any help!
I use two external monitors with SB and don't use the SB display when docked. I have them set to 100% and the SB set to 200%. However certain things will never scale right when going from one to the other (e.g. PowerPoint, Acrobat, Desktop icons, etc.). I've learned to "live" with shutting everything down and logging off and on when going to and from the dock (i.e. using external at 100% and native at 200%).
Alternatively you could leave SB open, set the external monitor as your secondary display and set the scaling individually. This will work, but the secondary display will be blurry somewhat.
Logging off and on wouldn't be too bad if it was only occasionally. But I dock and undock 4 or 5 times a day.

I'll have to try keeping SB on.

I use a SB and 2 external monitors running resolutions of 2560 x 1440. I use a reg hack to set alternate 3:2 aspect ratios for the SB display to run 1800 x 1200 or 1920 x 1280 and set the scaling at 100%. The SB display in not quite as sharp as I would like it, but it is better that dealing with applications that do not DPI scale well or at all.
Sorry if this is a silly question. If I were to get an Ultra HD monitor with a resolution such as 3480 x 2160, would that eliminate this scaling inconvenience? In other words, I could have both the Ultra HD monitor AND the Surface Book set to 200% scaling, so when I dock/undock there is no change in scaling?
I think will work with one, but not two UHD monitors because with two you are limited to 30Hz refresh rate
Thank! I'm curious...

1. What is the drawback of operating at 30Hz?

2. If I get a monitor that supports DisplayPort daisy chaining, is it still limited to 30Hz?
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Yes, more than one UHD monitor, whether daisy-chained or not, drops the refresh rate to 30Hz. It is due to a limitation in bandwidth of the video subsystems in the SB.

Most monitors run at a 60Hz refresh rate, meaning that the entire screen gets redrawn 60 times per second. If you are doing work that requires a lot of fast action and a great deal of motion on the screen, 30Hz won't handle the action as well as 60Hz, because the screen isn't being redrawn as quickly. This mostly impacts gamers as they need the higher refresh rates to be able to see very fast actions. Also, if your sensitive to it, you may notice a bit of screen flicker at 30Hz, though this doesn't bother most people. Because we use AC power for most of our lighting, the lights themselves flicker ever so slightly at 60Hz. You will typically not notice this with other light sources, such as a screen, because they are in sync. Since 30Hz is half of 60Hz, an even division, it's less likely that you'll see flicker at the lower rate.

One thing to keep in mind is that movies that are made on actual film, run at 24 frames per second, or 24Hz, so most people won't notice flicker on a screen until you get significantly below 24Hz.
Thanks for this great explanation!

So, 30Hz might be okay for me? I'm using Office, Adobe PhotoShop and InDesign for light work, and web browsing. How will 30Hz perform with these tasks?
So, I just picked up a single 4k monitor. If it works, my thinking was to get a second one. I've run it both at 30Hz and 59Hz (59Hz is what is defaulted to). I can totally tell the difference. Just moving the mouse cursor around the screen I can feel some lag. When typing in Word, there is an obvious lag in letters appearing on screen. Is this normal?

On the upside, docking and undocking is much smoother since having both monitors set at 200% scaling. Also, it's not perfect, but connecting through the Surface Dock is much more stable than with my other two monitors. Granted, I've only been using it for a few hours, so we'll see how this holds up.

So, now I'm contemplating a new plan.
  1. Instead of getting a second 4k UHD monitor, use a 2560 x 1440 (WQHD) monitor. I believe the Surface Book would be able to drive one UHD and one WQHD at 60Hz?
  2. How would Windows 10 handle scaling in the case of one UHD and one WQHD? I'm assuming that when I undock, the Surface Book would continue to use the scaling setting of the external display that was set as PRIMARY? In other words, if the UHD monitor was 200% scaling and the WQHD monitor was 125% scaling, when I undock the Surface Book, it will maintain the 200% scaling setting of the primary monitor, so no need to sign in and out. Am I thinking right about this?
Hmm...while I haven't spent much time on a monitor running at 30Hz, I didn't really notice a difference. I'm surprised that you are seeing as big a difference as you are and suspect that something else may be going on.

As far as question 1 is concerned, I think that once you have a UHD resolution display connected that any additional monitors added are only going to be supported at 30Hz, but I'm not certain of this. The one thing in your favor, however, is the fact that you don't use the Clipboard display when you have your external monitors connected, so that should free up some bandwidth that may keep you running both monitors at 60Hz.

Do you have a friend with such a monitor that you could borrow to test with? If not, does the store where you got your UHD monitor have a decent return policy? If so you could pick one up there for testing.

For question no. 2, I think you're going to have to experiment on your own to figure this out. Unless someone here has already done this exact same thing, it's hard to predict what will actually happen. I will say this, however; in theory it sounds good.