G-Sync on a FreeSync monitor query?

Space Monkey · 5 Mar 2019 at 20:21

Hi guys,

With the recent news that some or many FreeSync monitors now work with GTX GPUs, whether that's with Nvidia's certification or not, my question is this, how does the experience fare with a GTX card on a FreeSync monitor vs a GTX card on a G-Sync monitor?

My noggin is telling me that it wouldn't be as good but I've no experience so would love some input?

TIA

Rroff · 5 Mar 2019 at 20:27

Depends a lot on the monitor and what features are actually important or noticeable to you.

Some FreeSync monitors work better than others - G-Sync monitors generally have a wider refresh range where G-Sync is in effect (30-165+Hz) while quite a few FS monitors have ranges like 40-90Hz, etc.

G-Sync generally has better low framerate behaviour though in a lot of cases if you are dropping into those framerates a lot then you won't get a great experience with either - this can include things like some FreeSync monitors showing increased motion blur or noticeable changes in brightness at lower framerates as well as some differences in latency. (Adaptive sync misuses the monitors self-refresh capabilities to function which has some limitations when it comes to handling low framerates not present with the G-Sync FPGA).

G-Sync generally has better compatibility with applications that use variations of Windowed modes and other methods of non-exclusive fullscreen mode.

Some G-Sync monitors can have problems with the way nVidia does adaptive overdrive which might result in noticeable flicker or judder on bright content in video playback.

The average mainstream consumer would probably be hard pressed to tell between them on a monitor that supported either technology reasonably well.

Space Monkey · 5 Mar 2019 at 20:37

@Rroff thanks, that's a good piece of insight.

I'm obviously considering a FS monitor as they are a lot cheaper, but if I'm going to run into troubles then it seems worth paying the extra.

So even with an Nvidia card I'll need to somehow check if the G-Sync monitor has any issues?

JediFragger · 5 Mar 2019 at 20:38

I came from an Acer XB271HU to an LG 34GK950F-B and the Gsync implementation has been flawless imo, as good as the Acer (at least so far!). Very happy

Rroff · 5 Mar 2019 at 20:39

Space Monkey said:
@Rroff thanks, that's a good piece of insight.

I'm obviously considering a FS monitor as they are a lot cheaper, but if I'm going to run into troubles then it seems worth paying the extra.

So even with an Nvidia card I'll need to somehow check if the G-Sync monitor has any issues?

TBH pretty much any monitor these days is worth researching - so many half-arsed designs and poor quality control - usually covered in detail in the appropriate thread here.

I certainly wouldn't be put off FreeSync just because there are some monitors that are subpar. Also so far nVidia have been quite quick surprisingly to address issues like flicker that happen(ed) on some FreeSync monitors with nVidia.

Space Monkey · 5 Mar 2019 at 20:39

JediFragger said:
I came from an Acer XB271HU to an LG 34GK950F-B and the Gsync implementation has been flawless imo, as good as the Acer (at least so far!). Very happy

So it still feels silky smooth?

JediFragger · 5 Mar 2019 at 20:41

Just make sure to do your research to make sure your chosen FS monitor works well with nVidia's method.

JediFragger · 5 Mar 2019 at 20:41

Space Monkey said:
So it still feels silky smooth?

Yup

Space Monkey · 5 Mar 2019 at 20:45

Thanks guys, I'll look into it some more, currently eyeing up the Alienware 240Hz monitors and there's £200 between them

Vexr · 5 Mar 2019 at 21:44

Quite a few GSync monitor owners are having ongoing issues with borderless full screen / windowed mode. I recently bought a FreeSync monitor for use on an NVidia card, and unfortunately I'm having the same problem with the vast majority of games. Exclusive full screen works great though, albeit with a quick flicker when/if transitioning across the LFC threshold (48 hz).

Just weird how the refresh rate never 'locks on' in borderless full screen/windowed; it's all over the place and flickers, yet it locks on fine in exclusive full screen. Certainly makes me think its a software issue.

Rroff · 5 Mar 2019 at 21:47

Vexr said:
Quite a few GSync monitor owners are having ongoing issues with borderless full screen / windowed mode. I recently bought a FreeSync monitor for use on an NVidia card, and unfortunately I'm having the same problem with the vast majority of games. Exclusive full screen works great though, albeit with a quick flicker when/if transitioning across the LFC threshold (48 hz).

Just weird how the refresh rate never 'locks on' in borderless full screen/windowed; it's all over the place and flickers, yet it locks on fine in exclusive full screen. Certainly makes me think its a software issue.

It isn't in an ideal place on either setup due to the way MS has implemented compositing in the Windows OS but having the FPGA allows nVidia to use a few tricks for better compatibility that current implementation of adaptive sync can't really do.

Vexr · 5 Mar 2019 at 23:36

Rroff said:
It isn't in an ideal place on either setup due to the way MS has implemented compositing in the Windows OS but having the FPGA allows nVidia to use a few tricks for better compatibility that current implementation of adaptive sync can't really do.

Yeah, I got the impression from skim reading elsewhere that the issues were primarily to do with MS and Win10. I think I also read that NVidia had been doing something with their drivers to get around it that MS didn't like, and got their hand slapped for it when they found out. Workarounds like shutting down Desktop Windows Manager didn't work for me, and older drivers that have worked for some GSync users aren't an option for FreeSync monitor users on NVidia cards.

I'm surprised how many games don't support exclusive full screen at all. I never took any notice before as I always used borderless windowed where available, but it's certainly become an issue now.

Space Monkey · 5 Mar 2019 at 23:44

So as I run all my games full screen, is that the best option or am I mis-reading it?

Rroff · 5 Mar 2019 at 23:49

Space Monkey said:
So as I run all my games full screen, is that the best option or am I mis-reading it?

Some games use a "fake" fullscreen which just hide the window borders/handles and place the game window on top of everything else - to varying degrees it doesn't work well with adaptive sync technologies until/unless MS makes some changes to the display model in Windows. It isn't a huge issue but you might find some games that do that FreeSync or G-Sync won't work.

Space Monkey · 5 Mar 2019 at 23:51

Ah, I never knew that, is there a way to check which games do that or is it a case of just trying each one?

Vexr · 6 Mar 2019 at 00:23

Space Monkey said:
Ah, I never knew that, is there a way to check which games do that or is it a case of just trying each one?

I don't think anyone has made a list. It's easy to tell in game by hitting the Windows key on your keyboard / alt tabbing. The only game I've tested so far that uses the fake borderless full screen and works fine with GSync-compatibility is Forza Horizon 4 - which just so happens to be a recent Microsoft game.

LadFromWales · 6 Mar 2019 at 01:16

The only main downside of G-Sync compatible vs a G-Sync monitor with the module, is that the module has variable pixel overdrive.
As the frame rate drops, your chosen overdrive setting will push too much voltage through the pixels for the now lower number of frames to render, causing overshoot.
Generally, a lower overdrive setting is recommended for framerates predominantly lower.
I am using 'fast' on my S2719DGF and see a little overshoot if I allow my FPS/Hz to drop towards 60, generally when panning the camera, but it is very subtle and I have to look for it.
I have noticed no flickering when transitioning over the LFC threshold. The GTA loading screen runs at around 60fps and the monitor is bouncing between 60 and 120 but there is no perceived flickering. Nvidia tends to enable LFC at higher Hz than AMD.

A monitor with a G-Sync module will dynamically adjust the overdrive as such that a drop in FPS/Hz will cause no (less?) overshoot.

@Vexr is FH4 a DX12 game? I believe exclusive fullscreen is dead with DX12? I didn't check if freesync was working while I was playing FH4 earlier, but I noticed no tearing while my framerate was always between 110 and 155.

Vexr · 6 Mar 2019 at 02:00

LadFromWales said:
@Vexr is FH4 a DX12 game? I believe exclusive fullscreen is dead with DX12? I didn't check if freesync was working while I was playing FH4 earlier, but I noticed no tearing while my framerate was always between 110 and 155.

Yes, FH4 is DX12. Exclusive full screen isn't quite dead on DX12 yet - Deus Ex: Mankind Divided, Rise of the Tomb Raider, and Shadow of the Tomb Raider for example all have exclusive full screen modes available while using it.

Borderless full screen seemed to prevent tearing without VSync IIRC as it has its own form of VSync + buffering independent of the game. I always preferred it on my non-sync monitor over exclusive full screen and that was part of the reason. FreeSync wouldn't deal with tearing when fps is over the monitors refresh rate (no idea what Hz your monitor is and whether you're describing FPS in FreeSync range or over the max). From what I've read, symptoms of FS/GS problems in borderless windowed may vary, but going by my experience FH4 is fine with it anyway.

DereksDontRun · 6 Mar 2019 at 07:50

has anyone found a hack for 9 series cards and the new freesync compatibility? I have a 980ti and keep wondering about upping to a 1440 monitor

JediFragger · 6 Mar 2019 at 08:15

Space Monkey said:
So as I run all my games full screen, is that the best option or am I mis-reading it?

Use mine usually on Windowed (Fullscreen) so I can tab-out easier. Works fine

The Gsync version of Freesync even works fine on The Division, whereas AMD *still* can't get it working with that game. Shame on them imo, esp when nVidia can show them how it's done!!!!