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ASUS PG248Q : Calibration (gamma - brightness) - Scan lines - GSYNC tearing

Level 7
I recently bought an ASUS PG248Q (together with a whole new PC in fact) and decided to make a thread about it because it gave me some grey hairs setting it up properly. I ran into a lot of different problems other people are also experiencing.
Whether it has to do with ASUS, this model, 144Hz or GSYNC I leave in the middle but one thing is for sure my monitor out-of-box was really a very bad experience. I was at the point of RMA-ing it several times, but after 14 days of tweaking and experimenting I got it to a decent level, hence this guide.
Too bad I can't compare with other G-SYNC or 144Hz monitors.

My setup:

- Core i5-7500
- 16 GB RAM
- Gigabyte Geforce GTX 1060 6 GB

I connect my monitor via display port. Connecting via hdmi gave some other issues and I decided to focus only on the setup I was going to use.
I do not OC my monitor and keep it at 144Hz in the OSD menu. Overdrive Normal. Dark boost off.


I used these guides as a starting point:,4821.html

The default gamma and brightness are WAY WAY off. But in contrast to what these guides stated, my gamma was far to LOW instead of to high.
I also noticed a kind of 'warming-up'-effect, the gamma increases when the monitor is up for 'some' time.
Checked your gamma via :

I ended up with the following settings:
- monitor OSD brightness : 25
- monitor OSD gamma : 2.5
- Nvidia control panel gamma : RED (+0.86) , GREEN (+0.86), BLUE (+1.00)
(goto 'Adjust desktop colour settings' - 'Use Nvidia settings')

Scan lines / interlace pattern artifacts:

When enabling G-sync at 144Hz I noticed 'scan lines'. 1-2 pixel high mini shade-like waves, running from top to bottom over the screen.
The effect comes and goes but never dissappeared forever. It is also described in this review ( as interlace pattern artifacts.

I managed to fix this by lowering the monitor's refresh rate to 143,900Hz in the Nvidia control panel.
'Change resolution' - 'Select 1920-1080 and 144Hz' - 'Customise' - 'Enable resolutions ...' - 'Create custom Resolution' - 'Timing - Manual' - '143,900Hz'

G-SYNC tearing:

I noticed, as well as many other people with G-SYNC monitors, tearing in the bottom half of the screen while in the fps range where G-SYNC should be active (below 144fps). It is a nvidia driver problem.
It is described in detail in this thread : !!! READ IT !!!!
Conclusion, to obtain a tear-free low-input-lag experience you should:
- enable G-SYNC in the nvidia control panel
- enable V-SYNC in the nvidia control panel
- limit your framerate 2-3 fps below your monitor's refresh rate (mine is at 141 fps), preferably with the in-game framerate limiter otherwise with an external tool (rivatuner).

Let me know if you ran into the same issues as I did.

Level 12
Thanks for sharing this information with everyone, unfortunately majority of the G-SYNC monitors do have quite a few problems. A few of the other mentioned issues are due to panel limitations but we're looking into the issues further.

Checked your gamma via :

In order for the lighter and darker bands to blend in I have to go REALLY low, like 0.5 on red and green and 0.7 on blue. Everything looks really dark then.

sorry for digging this
I dont know why exactly this is happening when I play at 144hz the frames drop from 144 to 88 or 90 and while the drop I got tearing and get get killed in games lol

does anyone have better settings for shooter (180hz oc) ? The above things are very dark and you generally see bad opponents

My Setup :

i7 8700k - oc 5ghz 1.34v
ASUS ROG Maximus X Hero z370
ASUS ROG Strix GeForce GTX 1080 Ti - oc 2000/6000
16gb DDR4 3200


Hey guys,

Like many others, I had a horrible experience with my PG248Q out of the box...Brightness was ludicrously high, colour gradients looked awful, especially darks and grays, which seemed to be crazy pixellated. I spent a long time reading the various threads here and elsewhere trying to make improvements. The problem is especially bad with YouTube vids, as others have noted, and the Westworld opening credits (seems like a common benchmark) looked absolutely terrible. My desktop background at the time I purchased the monitor was a Razer RBG kaleidoscopic image thing, and it looked HORRENDOUS out of the box, insane banding and pixellation around dark areas where they neared lighter areas. I was so sure the monitor was broken, but I've just discovered after much trial and error, that for me, it really was just extreme brightness.

I tried quite a few solutions, and of course every panel is a little different, but with a combo of Monitor OSD settings and the Nvidia Control Panel, I have managed to get the colour issues more or less resolved. I also have a Phillips Brilliance PHL241B7Q, an IPS panel with good colour accuracy and reproduction, and I used it to test various videos of various quality, side-by-side, from YouTube to Bluray. I've been testing now for a couple of hours and everything looks OK...I've managed to get the PG248Q looking something close to the Phillips panel in all applications, from browsing, to watching videos, to simply comparing the representation of colours of various desktop backgrounds on each monitor. Lagom black test looks good, however there is still a slight issue on the white test, with the final checkerboard being essential invisible, but it is entirely manageable.

I'll outline my monitor and Nvidia control panel setting below, hope it helps someone with the extreme brightness issue. It really can be made to look quite acceptably close to a good IPS, it just takes patience. Your settings may vary wildly, but the panel can be made to look good. God speed!

Monitor OSD settings:

Brightness - 35
Contrast - 45
Gamma - 2.5

Still in monitor OSD settings, I manually set Colour Temp to User Mode with the following RGB settings:

Red - 97
Green - 92
Blue - 100

Then finally in the Nvidia Control Panel settings:

Brightness - 55
Contrast - 32
Gamma - 0.95

Digital Vibrance - 55

** In the final image below, you can see that the yellowish tinge that appears in the other images is a function of me holding the camera lens slightly off to the right to get both monitors in the pic. From straight on viewing angle, the yellow shift is basically non-existent.

Hey guys, so while I managed to get my display looking pretty good, I kept looking around the net for new info, and I found a thread on the Geforce forums about enabling dithering with Nvidia cards in Windows. Nvidia GPUs have a dithering toggle option in the NVCP on Linux and Windows Server, but it's not in the regular Windows version, despite people requesting it for a long time.

A forum user on Geforce found the dithering registry keys that work in Linux actually work when manually applied in W10, so I read through the entire thread, and it worked for a lot of people. My PG248 has never looked this good, banding is visible only in terrible source material. Bluray and other well encoded video and images look amazing now. Obviously I still have my previously listed gamma/brightness settings in place. This registry key merely adds temporal dithering to the image already there, so your gamma and brightness need to be calibrated.

This is the forum link, your mileage may vary with the technique, I went with 8 bit temporal dithering and I can't believe it actually works. It even persists after playing games in Fullscreen, and after a soft and hard reboot, but some people are finding that they lose dithering after gaming. A simple reboot is enough to kick it back in for those who experience this behaviour. Anyhoo, read the thread carefully, and give it a shot.

Good luck!

Level 7
Thank you for this guide I been trying all kinds of settings since I got the monitor the other day and your setting fixed all the colour/gamma washout issues I was having. I just find it odd the monitor looks good over the hdmi port with some light OSD adjustments (R97 G92 B100) but the second I was on the displayport input the gamma went through the roof to the point I was getting image burn where I could see the overwatch login symbol once it went to the main menu for a second or too and your settings even solved this.*

And Bahz I'm just curious if the gamma settings is a software or hardware issue. And if there's any official news from asus on this matter*