NX-VUE24 Freesync 144hz - How To Force Display Scaling?

Everything about displays and monitors. 120Hz, 144Hz, 240Hz, 4K, 1440p, input lag, display shopping, monitor purchase decisions, compare, versus, debate, and more. Questions? Just ask!
Post Reply
User avatar
ball2hi
Posts: 31
Joined: 22 Nov 2016, 18:41

NX-VUE24 Freesync 144hz - How To Force Display Scaling?

Post by ball2hi » 21 Jan 2018, 00:02

I've noticed that, even with **GPU Scaling** disabled in my AMD settings, this monitor still is scaling the image. It **constantly** runs at 1920x1080 144hz when I select lower resolutions.

I can manually input 1280x720 @ 144hz in my CRU extension block settings and it'll have the monitor report 1280x720 @ 144hz but idk if that's being display scaled or not.

Do I have to add resolutions / refresh rates as standard resolutions?

User avatar
Chief Blur Buster
Site Admin
Posts: 11647
Joined: 05 Dec 2013, 15:44
Location: Toronto / Hamilton, Ontario, Canada
Contact:

Re: NX-VUE24 Freesync 144hz - How To Force Display Scaling?

Post by Chief Blur Buster » 21 Jan 2018, 00:08

Yes, that's monitor scaling, instead of GPU scaling.

Forcing lower-resolutions to run windowboxed is not always easy. The feature often has to be built-in into the monitors. Some gaming monitors have a mode that allows you to configure this (under different terminology, e.g. "1:1 Mapping" or "Unscaled" etc). This is very monitor dependent.

It's much easier to do this via graphics drivers, if you're able to force the graphics driver to center an 800x600 in the middle of a real 1920x1080 signal. But this feature is not always possible -- this feature was often available in NVIDIA Control Panel years ago before it became less flexible especially whenever certain modes (e.g. GSYNC) was enabled. At the time you could set "No Scaling" and then select "Perform Scaling on GPU" and then enable the "Override" checkbox. I believe it stopped working when GSYNC was enabled: It only worked scaled to full screen.

So, perhaps, try turning off FreeSync temporarily, before doing this. Not all VRR monitors can do 1:1 pixel mapping in low-resolution while keeping VRR enabled.

Trick for Stubborn Monitors that has no 1:1 Pixel Mapping feature
(Warning: this will not always work)


Occasionally you can trick a monitor to avoid scaling by using CRU 1080p timings and windowboxing a lower resolution within it. Try using ToastyX CRU instead of NVIDIA/AMD for this.

Basically
1. Write down all the numbers of your working 1920x1080 mode.
2. Transfer some "Active" equally to "Front Porch and "Back Porch". For every 2 pixels Active you remove, add 1 each to Front & Back.
3. Do step #2 separately for Horizontal and for Vertical.
4. Your Sync, Totals, Refresh Rate, and Dotclock should be unchanged.
5. Save this mode.

For example, if you're reducing 1920x1080 down to 800x600 windowboxed in the centre of your screen -- 1:1 pixel mapped (no scaling).... Then for creating a custom resolution mode -- you want to add ((1920-800)/2) = 560 each to both Horizontal Front Porch and Back Porch. And add ((1080-600)/2) 240 each to both Vertical Front Porch and Back Porch. Horizontal Active 800 and Vertical Active 600. Now you've created 800x600 using 1080p timings. Try sending it to the monitor, and if it tricks the monitor to stop scaling the mode.

This does not always work on all monitors, but it works on some of them (or at least via some inputs, such as DVI). This trick worked via VGA inputs in the old days but sometimes newer monitors just latch onto the active's and scale it anyway. So sometimes this trick doesn't work.
Head of Blur Busters - BlurBusters.com | TestUFO.com | Follow @BlurBusters on Twitter

Image
Forum Rules wrote:  1. Rule #1: Be Nice. This is published forum rule #1. Even To Newbies & People You Disagree With!
  2. Please report rule violations If you see a post that violates forum rules, then report the post.
  3. ALWAYS respect indie testers here. See how indies are bootstrapping Blur Busters research!

User avatar
ball2hi
Posts: 31
Joined: 22 Nov 2016, 18:41

Re: NX-VUE24 Freesync 144hz - How To Force Display Scaling?

Post by ball2hi » 21 Jan 2018, 00:22

Wow! Thanks for the quick response!

I noticed that, if I delete the main Detail Resolution (which also disables FreeSync) I can add other resolutions in the extension block like 1280x720. If I play a game at 1280x720, the monitor will then report at 1280x720.

Would it be more/less beneficial in terms of lag or pixel accuracy to leave my CRU alone and let it report 1920x1080 all the time or force a 1280x720 into the resolution so that it's reporting 1280x720 when I use that resolution?

Also, my monitor has two 1920x1080 resolutions in CRU. One in the main detailed resolution and one in the extension block.

Main: https://cdn.discordapp.com/attachments/ ... nknown.png

Extension: https://cdn.discordapp.com/attachments/ ... nknown.png

User avatar
Chief Blur Buster
Site Admin
Posts: 11647
Joined: 05 Dec 2013, 15:44
Location: Toronto / Hamilton, Ontario, Canada
Contact:

Re: NX-VUE24 Freesync 144hz - How To Force Display Scaling?

Post by Chief Blur Buster » 21 Jan 2018, 00:26

For scaling lag, it depends on the monitor.
-- I've seen GPU scaling have less lag
-- I've seen monitor scaling have less lag
-- I've seen both become essentially lagless on some monitors and GPUs

In the past, GPU scaling used to have more lag since it was done on a full-framebuffer basis.

But that's not necessarily true anymore ever since GPU scaling became very fast. Basically, the best GPU scaling is nowadays line-buffered (essentially lagless) which is less than the more inefficient (full-frame-buffered) monitor scalers. So I don't know if you'll be more lagless with or without GPU scaling.

In many cases there's no difference. Most eSports monitors now use line-buffered scalers (but not all of them).

For 1:1 pixel mapping, it typically doesn't matter as long as it works. 1:1 pixel mapping tends to add no latency no matter how it's done -- windowboxed resolutions have the same lag as the full resolution for a physical pixel-versus-pixel basis (e.g. center of screen has same lag)
Head of Blur Busters - BlurBusters.com | TestUFO.com | Follow @BlurBusters on Twitter

Image
Forum Rules wrote:  1. Rule #1: Be Nice. This is published forum rule #1. Even To Newbies & People You Disagree With!
  2. Please report rule violations If you see a post that violates forum rules, then report the post.
  3. ALWAYS respect indie testers here. See how indies are bootstrapping Blur Busters research!

User avatar
RealNC
Site Admin
Posts: 3741
Joined: 24 Dec 2013, 18:32
Contact:

Re: NX-VUE24 Freesync 144hz - How To Force Display Scaling?

Post by RealNC » 21 Jan 2018, 01:42

NVidia cards have a discreet scaler on them. It's non-programmable and consumer cards (GeForce) only do bilinear scaling. Pro-grade cards (Quadro) do bicubic and other methods. It seems to be near-instant and thus completely lag-free, although to be sure someone would need to run some lag tests on different card generations to see if the scaler changed over the years.

However, quality isn't good with consumer cards. Bilinear is very blurry. Monitor scalers usually do sharper scaling, but you run the risk of higher input lag. I remember someone here having tested a BenQ gaming monitor from the XL series (I think) and monitor scaling added a full frame of lag. So it's also a tradeoff between quality and input lag.

For lowest-lag scaling (CS:GO and such) GPU scaling should be the safest bet. If you want higher scaling quality, you should test display scaling.

Unfortunately, monitor review sites that run input lag tests never bother with testing the scaler's input lag too. Even if a monitor is tested with near-zero input lag (like the BenQ in question), doing display scaling on it might double or triple the input lag. We just don't know because nobody tests that. They only test the native resolution.

Similarly, graphics card reviews never test scaling lag. So we don't have much info on that front either. There's been a few testers out there doing input lag tests for GPU scaling for NVidia and finding no increase in input lag, but it was years ago. The more recent NVidia cards might as well have changed their scalers.

So really, we're mostly in the dark here. Unless tests are performed, we can only take an educated guess and consider GPU scaling the preferred method when it comes to input lag. Without any proof.
SteamGitHubStack Overflow
The views and opinions expressed in my posts are my own and do not necessarily reflect the official policy or position of Blur Busters.

User avatar
Chief Blur Buster
Site Admin
Posts: 11647
Joined: 05 Dec 2013, 15:44
Location: Toronto / Hamilton, Ontario, Canada
Contact:

Re: NX-VUE24 Freesync 144hz - How To Force Display Scaling?

Post by Chief Blur Buster » 21 Jan 2018, 14:31

This generally is true. Modern GPU scalers now have reliably now lag, while monitor scalers are a wildcard. The tables have turned. Roll your dice.
Head of Blur Busters - BlurBusters.com | TestUFO.com | Follow @BlurBusters on Twitter

Image
Forum Rules wrote:  1. Rule #1: Be Nice. This is published forum rule #1. Even To Newbies & People You Disagree With!
  2. Please report rule violations If you see a post that violates forum rules, then report the post.
  3. ALWAYS respect indie testers here. See how indies are bootstrapping Blur Busters research!

Post Reply