Talk about NVIDIA G-SYNC, a variable refresh rate (VRR) technology. G-SYNC eliminates stutters, tearing, and reduces input lag.
List of G-SYNC Monitors.
-
jorimt
- Posts: 2641
- Joined: 04 Nov 2016, 10:44
- Location: USA
Post
by jorimt » 29 Jan 2019, 19:44
Notty_PT wrote:In that case I have no idea why I notice the input lag increase on all of my Asus monitors when I enable VRR. I may give up trying to find out why at this point lol. But it totally doesn´t happen on the Samsung CFG73 and I´m waiting on my MSi Optix MAG241C to see what happens.
Granted, I didn't say that was the case, just that it was "possible."
If we're still talking G-SYNC compatible on FreeSync monitors, what's is even more likely to be causing the lag you perceive in G-SYNC mode is the driver interaction with your specific test display(s) and system.
This driver feature is indeed very new, and has room to mature over time.
(jorimt: /jor-uhm-tee/)
Author: Blur Busters "G-SYNC 101" Series
Displays: ASUS PG27AQN, LG 48C4 OS: Windows 11 Pro Case: Fractal Design Torrent PSU: Seasonic PRIME TX-1000 MB: ASUS Z790 Hero CPU: Intel i9-13900k w/Noctua NH-U12A GPU: GIGABYTE RTX 4090 GAMING OC RAM: 32GB G.SKILL Trident Z5 DDR5 6400MHz CL32 SSDs: 2TB WD_BLACK SN850 (OS), 4TB WD_BLACK SN850X (Games) Keyboard: Wooting 60HE Mouse: Razer Viper Mini SE Sound: Creative Sound Blaster Katana V2 VR: Beyond 2, Quest 3, Reverb G2, Index Consoles: Dreamcast, PS2, PS3, PS5, Switch 2, Wii, Xbox, Analogue Pocket + Dock Scaler: RetroTINK 4k
-
Chief Blur Buster
- Site Admin
- Posts: 12266
- Joined: 05 Dec 2013, 15:44
- Location: Toronto / Hamilton, Ontario, Canada
-
Contact:
Post
by Chief Blur Buster » 29 Jan 2019, 23:41
VRR requires extremely close integration between graphics drivers and the monitor. The input lag of a VRR display is also dependant on graphics drivers too (much, much, moreso than it is for VSYNC OFF) and there are potential issues that can pop up (driver-specific, monitor-specific, weird interactions, etc). The monitor is slaving refresh cycles to the graphics driver, and it's the graphics drivers responsibility to properly deliver the refresh cycles as quickly as the game demands that it be delivered to the monitor. There can be all sorts of issues that unexpectedly slow down the delivery of the refresh cycle.
-
Jesse Durden
- Posts: 5
- Joined: 29 Jan 2019, 12:55
Post
by Jesse Durden » 01 Feb 2019, 05:05
Update: I tested a MAG241C FreeSync monitor and it requires a 120fps limit to prevent all tearing. This is vs the 110-100 limit required for my VG279Q.
So there is definitely a difference in implementation between monitors.
-
andrelip
- Posts: 178
- Joined: 21 Mar 2014, 17:50
Post
by andrelip » 01 Feb 2019, 09:30
Just to sum up: Alienware AW2518HF (freesync 240hz) have known issues of overshooting when using with NVIDIA without gsync that is not presented in RX series (just look at the videos on youtube). I have double checked the timings using CRU to make sure both brands uses the same. For NVIDIA Windows 10 display recognizes as 239 HZ and for AMD as 240hz (but in the dropdown option is 240). If I set CRU to use 240hz with LCD reduced blank then I get rid of overshooting even in the FASTER overdrive but that always results in frameskip (only perceived with a high speed camera on Blurbuster test). Using the new G-SYNC with freesync compatibility removes the overshooting while in the AMD freesync is not necessary. In my perception 300 FPS with g-sync enabled delivers the "right" 240hz mode for the display and have a better latency than using 300@240hz with fixed frequency. Since the video of battle(non)sense now I'm sure that the better setting for low input lag is to enable freesync and uncap fps.
-
RealNC
- Site Admin
- Posts: 4613
- Joined: 24 Dec 2013, 18:32
-
Contact:
Post
by RealNC » 01 Feb 2019, 12:50
I guess this means people at last have a good reason to be waiting for nvidia driver updates with bated breath

Steam •
GitHub •
Stack 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.
-
Notty_PT
- Posts: 552
- Joined: 09 Aug 2017, 02:50
Post
by Notty_PT » 02 Feb 2019, 10:53
Jesse Durden wrote:Update: I tested a MAG241C FreeSync monitor and it requires a 120fps limit to prevent all tearing. This is vs the 110-100 limit required for my VG279Q.
So there is definitely a difference in implementation between monitors.
Are you sure is not the game you tested? The gsync on my mag241c worked even better than on supossely official gsync monitors lol
-
Jesse Durden
- Posts: 5
- Joined: 29 Jan 2019, 12:55
Post
by Jesse Durden » 02 Feb 2019, 11:15
Notty_PT wrote:Jesse Durden wrote:Update: I tested a MAG241C FreeSync monitor and it requires a 120fps limit to prevent all tearing. This is vs the 110-100 limit required for my VG279Q.
So there is definitely a difference in implementation between monitors.
Are you sure is not the game you tested? The gsync on my mag241c worked even better than on supossely official gsync monitors lol
I'm not testing with a game, I'm using the Nvidia Pendulum demo because it lets you easily see the tears. You can test yours yourself with this procedure:
https://www.reddit.com/r/Monitors/comme ... l_tearing/
-
Notty_PT
- Posts: 552
- Joined: 09 Aug 2017, 02:50
Post
by Notty_PT » 02 Feb 2019, 18:20
andrelip wrote:Just to sum up: Alienware AW2518HF (freesync 240hz) have known issues of overshooting when using with NVIDIA without gsync that is not presented in RX series (just look at the videos on youtube). I have double checked the timings using CRU to make sure both brands uses the same. For NVIDIA Windows 10 display recognizes as 239 HZ and for AMD as 240hz (but in the dropdown option is 240). If I set CRU to use 240hz with LCD reduced blank then I get rid of overshooting even in the FASTER overdrive but that always results in frameskip (only perceived with a high speed camera on Blurbuster test). Using the new G-SYNC with freesync compatibility removes the overshooting while in the AMD freesync is not necessary. In my perception 300 FPS with g-sync enabled delivers the "right" 240hz mode for the display and have a better latency than using 300@240hz with fixed frequency. Since the video of battle(non)sense now I'm sure that the better setting for low input lag is to enable freesync and uncap fps.
That battlenonsense video was made with a VG258qr wich has known input lag issues so is not a good representation of gsync input lag! And if you use 300fps @ 240hz you are not getting any VRR and 60 fps are missing because monitor cant handle wich creates judder!
-
andrelip
- Posts: 178
- Joined: 21 Mar 2014, 17:50
Post
by andrelip » 07 Feb 2019, 21:27
Notty_PT wrote:andrelip wrote:Just to sum up: Alienware AW2518HF (freesync 240hz) have known issues of overshooting when using with NVIDIA without gsync that is not presented in RX series (just look at the videos on youtube). I have double checked the timings using CRU to make sure both brands uses the same. For NVIDIA Windows 10 display recognizes as 239 HZ and for AMD as 240hz (but in the dropdown option is 240). If I set CRU to use 240hz with LCD reduced blank then I get rid of overshooting even in the FASTER overdrive but that always results in frameskip (only perceived with a high speed camera on Blurbuster test). Using the new G-SYNC with freesync compatibility removes the overshooting while in the AMD freesync is not necessary. In my perception 300 FPS with g-sync enabled delivers the "right" 240hz mode for the display and have a better latency than using 300@240hz with fixed frequency. Since the video of battle(non)sense now I'm sure that the better setting for low input lag is to enable freesync and uncap fps.
That battlenonsense video was made with a VG258qr wich has known input lag issues so is not a good representation of gsync input lag! And if you use 300fps @ 240hz you are not getting any VRR and 60 fps are missing because monitor cant handle wich creates judder!
Fixed 240hz (no freesync) have ghost and overshooting problems. When I got 240hz with freesync on I have none of those problems. Also I usually measure my input lag by using humanbenchmark.com. It's not perfect but in my Hackingtosh (same pc with gtx 1080) my best scores usually are around 230ms (it only support 144hz and the display scanout could have a little buffer). Using Windows 10 and fixed 240hz I have 170ms average with some lucky shots between 165~170ms. With G-sync on I can do an average of 155ms with some 140~150ms clicks. It's not a perfect tool for testing but at least it is accessible and do the job for simple comparisons.
-
InBetweenNames
- Posts: 15
- Joined: 07 Feb 2019, 21:31
Post
by InBetweenNames » 07 Feb 2019, 21:36
I also have the AW2518HF with a GTX 1080 Ti (Founders), and I can also confirm that the overdrive is much better with G-Sync Compatible enabled. However, I have no real way of testing latency. All I know is it feels better to use. For the record, I have an average 60% accuracy with Widowmaker in Overwatch and 18-19% scoped critical. It would be really cool if someone with the means were able to test this monitor and post the results, because I'm all about the latency reduction.