Per-Display Scaling is Blurry RRS feed

  • Question

  • I have a Lenovo Yoga 2 Pro which has a resolution of 3200 x 1800 which I run at 200% scaling.

    I have just bought an Asus PB278Q which has a resolution of 2560 x 1440 which I run at 100% scaling, and which I want to use for development.

    However, all content on the external display is blurry.

    So I tried the option for setting one scaling of 100% for all displays and now the external display is sharp as it should be, but the internal display is obviously useless in desktop mode because everything is too small. I verified that the external display is being driven at the correct resolution via the monitor's own information option which says 2560 x 1440 at 60Hz (I was at least pleased that the Intel HD 4400 graphics were able to drive both displays at their proper resolution with 32-bit colour and at 60Hz). I have a fully updated version of Windows 8.1 Pro Update 1.

    So my guess is that Windows is rendering my external display off-screen at 200% and then crunching it down to 100% via bitmap processing.

    Is this how Microsoft have implemented per-display scaling? There is no way I can tolerate such blurriness on the external display especially as I intend to use it mainly for development so clarity of text is important.

    I've posted to this forum in the hope there will be other people with a similar setup. Is anyone able to help resolve this or is it simply a bad implementation of per-display scaling?

    Here are a couple of comparison screenshots of the external display showing File Explorer and Visual Studio 2013:

    Mixed scaling - internal display at 200%, external display at 100%

    One scaling at 100%

    Comparison Picture
    • Edited by i-am-andrew Saturday, April 12, 2014 1:24 PM
    Friday, April 11, 2014 4:10 PM

All replies

  • Hi,

    Please refer to the contents of the link below to set your dual monitor resolution for test.

    Guided Help: Dual monitor setup is easy in Windows 7!:

    Roger Lu
    TechNet Community Support

    Monday, April 14, 2014 9:09 AM
  • Hello, this link only seems to show how to extend the desktop on to multiple monitors which I know how to do!

    The problem I have found is Windows 8.1 per-display scaling appears to use bitmap resizing rather than rendering normally to a properly scaled display. This results in significant blur which strains your eyes trying to read text for any length of time. This is a fundamentally flawed approach and as I have found in actual use it makes per-display functionality near-useless

    Monday, April 14, 2014 12:26 PM
  • So my guess is that Windows is rendering my external display off-screen at 200% and then crunching it down to 100% via bitmap processing.

    Previous guesses were about ClearType and the change from multi-color pixel interpolation down to just grey-scale pixel interpolation.  Supposedly this was the answer to complaints about color fringes caused by ClearType and also to solve related problems when tilting Tablets from Landscape into Portrait orientation.


    (Apparently the proper keywords instead of my interpretation of these details is sub-pixel anti-aliasing, grayscale or color.)

    FWIW my workaround in IE is always to use a Zoom higher than 100%.  Another thing that helped was choosing a resolution for my wide-screen monitor which matched the aspect ratio of my Tablet, though I don't know if that was just a coincidence or just an example of changing the DPI on the wide-screen monitor to be something less than its "native resolution".  Instead of calling the text "blurry" I would call it "patchy", until a sufficient Zoom factor gets applied to fill in the holes.  A related factor I think is color.  E.g. all the crazy pastel font choices must surely make a difference about how many "holes" there are to fill in?

    Robert Aldwinckle

    Monday, April 14, 2014 2:40 PM
  • The only workaround I found was to drive the built-in display at half the resolution 1600 x 900 so that I could run all displays at 100% scaling. However this obviously throws away the benefits of using a high dpi display, even when the external display is no longer attached. Beyond that, changing screen resolution settings everytime would be a pain.

    Anyway I've returned the monitor now because per-display scaling in Windows is clearly not a viable option for prolonged use with lots of text such as development. It's a big shame and Microsoft need to rethink their approach, it just isn't good enough.

    (btw if you're viewing the sample pictures in IE at anything other than 100%, the introduction of blurriness in the per-display scaling won't be as obvious, you could try viewing the picture in paint instead to avoid additional anti-aliasing when zooming it)
    Monday, April 14, 2014 2:54 PM
  • Hi Andrew,

    I know exactly what you're talking about. I have a Lenovo Thinkpad Yoga with a 12.5" Full HD screen and an external 22" display at 1680 x 1050. When the laptop arrived, the scaling was set at 150%, and it worked and looked perfect. After plugging in my external display I noticed the horrible blurry text and other items on the external display, however the window boarders and some controls appeared to scale fine.

    Since then I've settled on 125% across both screens as 100% is clearly too small for a Full HD 12.5" display, and 150% is WAAAY to large on my external display (the advantage of having an external display was basically ZERO). I couldn't handle the poor scaling and was a bit baffled by the raving reviews on how awesome it was that Windows 8.1 handled different PPI screens "properly". I struggle with a small Full HD display, I don't even want to know what it's like with anything finer!!

    Here's hoping something comes of this in the next update..?!

    Wednesday, May 7, 2014 1:15 PM
  • Bump for this issue

    I have a Dell XPS 15 (9530) 3200 x 1800 and using an extended monitor (21'' FHD). The scaling applied is at 200%. The laptop screen looks fine but the extended monitor is borderline unusable.

    The IE 11 menus are huge on the external monitor. All other apps that are optimized for hidpi displays are blurry (both text and menu times - though menu item sizes are visually uniform in size on both laptop and external display). But the blurry text is kinda killing the experience - I use mainly the laptop screen now.

    The programs that look blurry on the external screen: Firefox, Chrome, Notepad++, everything in MS Office.

    But there is one program that does not look blurry on the external display: Codeplex Terminals ( I don't know how they did it but even the icons look the same size on both monitors and text is sharp.

    Thursday, September 18, 2014 10:04 AM
  • I have a similar problem myself. I have a Lenovo Y50 Laptop with 15.6" UHD display (3840x2160), with a dell 21" external monitor (1920x1200). Laptop must be run at 200% DPI scaling to make UI elements on the laptop large enough to be usable. When the external monitor is run with 100% DPI scaling everything is sized correctly but unusably blurry.

    Choosing a common scaling factor for both displays is not a solution either. Menu bars are excessively large and use up all the screen real estate on the external monitor when UI elements are scaled to over 100% and UI elements are too small to use when the laptop is run at below 200% DPI scaling.

    Even running one monitor at a time is not viable, as it requires logging in and logging out in order to change the DPI settings every time I intend to switch to or from using the laptop on my desk with an external monitor.

    It's extremely deceptive for Windows 8 to advertise that it can handle DPI scaling on multiple monitors as if it's a usable feature. I hope Microsoft releases a fix in the next service pack but doubt it will happen until Windows 9 at the earliest.

    Saturday, October 11, 2014 1:43 AM
  • Bump again. I have a setup with a 50" 4K TV and 2 27" 1080p monitors. I am stuck putting my tv in 1080p and let the TV upscale so i can have the same DPI scaling everywhere. Otherwise, my two monitors look horribly blurry, even after a log off/ log in. Having 100% of a 4K TV is also horrible because everything will then just be very tiny. It is also the same behavior in Windows 10. I was hoping it would be fixed in this preview build.. Not yet it seems. 
    • Edited by dgiaffe Tuesday, January 27, 2015 6:26 AM
    Tuesday, January 27, 2015 6:25 AM
  • Bump :D

    Having a Surface Pro 3. Nice sharp resolution! Plugged in one of my 1920x1200 Dell's and it's blurry. Disabling the automatic scaling and setting it to 100% looks pretty fine on my external, but the Surface now is unusable without a microscope!

    Tuesday, February 3, 2015 7:12 PM
  • I have the same problem. My setup is a Dell laptop with a 15.6" UHD 3840x2160 display, which looks fine using the default scaling settings. However, when I connected two external monitors, each is 20.1" @ 1600x1200, everything looks blurry on the external monitors. Changing the scaling to be the same across all displays has the same effect as what others have described in this thread.

    One thing I noticed though, is that if I RDP into another machine and set the RDP connection display to 1600x1200, I get sharp text on the external monitors. I can actually see blurry text using Windows Explorer open on the laptop, and right beside it sharp text of Windows Explorer inside the RDP session on the remote machine, all on the same monitor!

    Another thing I noticed is that the experience is reversed when using applications that are non DPI-aware, e.g. Computer Management (actually any MMC-based app). In those cases the app looks blurry on the main laptop display (because Windows is bitmap-scaling it), but if I move it across to one of the external displays its text looks crystal sharp!

    I found out that there are  3 types of apps:

    1) per-monitor DPI aware apps, e.g. IE 11 and Task Manager. Those do not change their scaling when dragged across from the high-res display to the low-res display, causing them to be huge wasting a lot of space.

    2) System-wide DPI aware apps, e.g. Windows Explorer, Notepad++, Visual Studio, Word, etc. Those change their scaling when dragged across, but their text becomes very blurry causing strain to the eyes.

    3) Non DPI aware apps, e.g. MMC-based apps. Those look blurry on the high-res display, and sharp on the low-res display.

    Somebody needs to figure this out and and fix it please.


    Thursday, May 7, 2015 8:58 PM
  • Bump

    Me too.

    But, here is what I'll add.  When I bring my running / booted Yoga 900 into the office and connect it to my Acer 1920 X 1080 display, things on the 2nd display are blurry.  I have to reboot with the 1920 X 1080 connected, then things are fine.  

    If I disconnect the <g class="gr_ gr_313 gr-alert gr_gramm gr_run_anim Punctuation only-del replaceWithoutSep" data-gr-id="313" id="313">display,</g> and go back to the Yoga 4K display, things are again somewhat blurry (not as bad as "the other direction), and, again, requires a reboot.

    I've lost all my "portability" features because of this - I can't just "yank" my computer and go.


    Tuesday, November 1, 2016 12:36 PM