G-Sync flickering on loading screens

[cen1]

Interesting read: http://www.pcper.com/reviews/Editorial/Look-Reported-G-Sync-Display-Flickering

Completely stopping the panel refresh would result in all TN pixels bleeding towards white, so G-Sync has a built-in failsafe to prevent this by forcing a redraw every ~33 msec. What you are seeing are the pixels intermittently bleeding towards white and periodically being pulled back down to the appropriate brightness by a scan.

It seems to me that simply lowering the 33ms forced refresh would solve the problem but who knows what else lurks behind the scenes.

 

[96Firebird]

33ms = 30FPS. I don't see how this can be solved if it is the fault of the TN pixel. Does IPS suffer the same issue? Probably a reason why G-sync only goes down to 30Hz. Wonder how Free-sync will combat this issue, if it shows up in any TN monitors.

If you refresh faster than 33ms, you are essentially above 30Hz and no longer matching the FPS if you are at 30FPS. You could potentially double the refreshes per frame sent (so refresh the screen at 60Hz when the GPU is sending 30FPS), but who knows how many more problems that would introduce...

 

[bystander36]

There are a couple possibilities. For starters, the actual point where it is a problem is just below 20hz, but they used 30hz as a safety net (they are saying it is much higher than that in this article...I guess previous articles were wrong?). They could some how, force double refreshes for a single frame, if the FPS drops below 30.

 

[Flapdrol1337]

They could set the lower treshold higher, like 40 fps or something, but that might negatively impact gameplay, a bit of flicker is probably less annoying than massive stutter at lower fps.

 

[cen1]

I totally missed the point that 33ms=30FPS so this doesn't really make any sense.. 30FPS would not produce such flicker because if it did, it would flicker all the time.
It definitely must be the second part that is causing the visibility of it:

An additional thing that’s happening here is an apparent rise in average brightness during the event. We are still researching the cause of this on our end, but this brightness increase certainly helps to draw attention to the flicker event, making it even more perceptible to those who might have not otherwise noticed it.

I can imagine that sudden increase in brightness would be noticeable at 30FPS.

 

[96Firebird]

I totally missed the point that 33ms=30FPS so this doesn't really make any sense.. 30FPS would not produce such flicker because if it did, it would flicker all the time.
It definitely must be the second part that is causing the visibility of it:

I can imagine that sudden increase in brightness would be noticeable at 30FPS.

How so? Flicker isn't seen on a normal display at 30FPS because the screen is still refreshing at 60Hz (or higher, whatever it is capable of). This means the pixel is being refreshed before it starts turning white.

Unless you mean it would flicker all the time on a G-sync display running at 30FPS? During gameplay you probably wouldn't notice it as much as you would on a static screen, such as a loading screen. I've never seen it in person though.

 

[rgallant]

"
December 3, 2014 | 01:45 PM - Posted by Anonymous (not verified)
You gotta love the "it doesn't show up in the games I play" comment.
Sounds like my QA saying "the bug doesn't show up for me". Doesn't mean it doesn't exist... The job of a proper reviewer is to test as many games as possible, since, well, some people will end up playing different games than your usual favorite games. That is what is called a proper and complete review. (Especially all the time you had to play around with that thing). Ah, "internet journalism"... But of course, better write good things, otherwise, no new toy to "review". Lol."






you have to wonder if reviewers [+asus, +nv] did see the flicker and did not mention it.
imo wouldn't be a big deal if not for the $800.00 gaming monitor that should have been tested with games by nv.

 

[96Firebird]

Have any actual users reported seeing the flicker while gaming?

 

[tential]

Have any actual users reported seeing the flicker while gaming?

I'm skeptical myself. Gsync has been out awhile and we're only now hearing about this?
Surely someone has seen a loading screen between then and now.

 

[96Firebird]

I think part of the reason we are not hearing about this during gaming is because most people are playing well above the 30FPS (therefore 30Hz) bottom limit. During loading screens, where the CPU/SSD/HDD are now the limiting factors, the FPS tanks and the screen runs at 30Hz. Add to that the static image, flicker is probably noticeable.

 

[bystander36]

A few final points before we go:

This is not limited to the ROG Swift. All variable refresh panels we have tested (including 4K) see this effect to a more or less degree than reported here. Again, this only occurs when games instantaneously drop to 0 FPS, and not when those games dip into low frame rates in a continuous fashion.
The effect is less perceptible (both visually and with recorded data) at lower maximum refresh rate settings.
The effect is not present at fixed refresh rates (G-Sync disabled or with non G-Sync panels).

As I suspected, it isn't a problem when the FPS are 30, but on static screens, it can instantly drop below 30 FPS, and perhaps in load screen, G-sync doesn't properly function.

 

[digitaldurandal]

As I suspected, it isn't a problem when the FPS are 30, but on static screens, it can instantly drop below 30 FPS, and perhaps in load screen, G-sync doesn't properly function.

Sounds like a driver issue to me, G-sync should have built in redraw before anyone sees flickering, why wait until the user notices it?

 

[bystander36]

Sounds like a driver issue to me, G-sync should have built in redraw before anyone sees flickering, why wait until the user notices it?

Ideally, yes, but there are problems with that approach, if you are too quick handed. Let's say you have a fairly solid 33ms frame times (30 FPS), then the frame time drops to 35ms, are you going to want to force an additional refresh, which forces a minimum of 8ms to the frame time? Probably not, they'd rather just wait it out instead.

Unfortunately, you have no idea before the next frame is given, how long you are going to wait without imposing latency. They do know if the frame you are waiting on will take 35ms or 1000ms. So when it instantly drops to 1 FPS, it can cause problems. Though I'd suspect, the 8 additional ms may not be so bad in comparison, but with 4k G-sync, that might mean 16ms additional time, which isn't acceptable.

 

[tidy]

.

 

[3DVagabond]

Have any actual users reported seeing the flicker while gaming?

I'm skeptical myself. Gsync has been out awhile and we're only now hearing about this?
Surely someone has seen a loading screen between then and now.

http://rog.asus.com/forum/showthread.php?50069-Swift-PG278Q-flickering

Hello.
Just got 3 new GSYNC 27` Monitors. In different games there are a constant "flickering"; tried all refresh rates, GSYNC on/off,original display port Cable .In 2D no problems at all (besides i cant connect the other 2 Monitors with my SLI Setup).
One of worst game

I have the exact same problem, i will also try banished and see if i can find a fix. Would suck to have spent big bucks if this will be a permanent issue.

Edit: Seems it's g-sync is the cause, the main reason people will buy it for.

I see g-sync related flickering on my screen when running pixperan-tests.
Perhaps a few of us have bad panels. It's problematic because not everyone seems to be able to notic

I also had flickering issues, and blurry text issues that just came out of no where after a couple of weeks use. The flickering went away in games with G-sync turned off, but text was still rough in appearance. Worked better in 120hz mode. I am using SLI gtx770 OC and 4770k OC @ 4.5ghz. My FPS is between 90-120 on bf4 with settings set to Nvidia optimum (GeForce experience - mix of ultra to medium). The overdrive Hz button doesn't really work either... My retailer picking it up today and starting the rma process. I suspect a faulty gsync module.

Mine was running fine - after getting a GTX 780ti OC - for a week. And now i have horizontal lines (shadows) on the bottom part of the screen, and very blurry text (looks like clutter on the fonts). Reading this forum (white on black) is very difficult. If i drag the browser window over on my other 2560x1440 (non ROG) monitor everything is sharp and clear again.
Setting 144hz makes the image more stable, at 60hz it more looks like horizontal stripes of noise. I will do a new rma (my 3rd) when the dealer gets new supplies again next week.

This issue is definitely related to using the G-Sync module.

I've head some people had luck uninstalling certain programs, but I've had no such luck.

I can confirm that uninstalling RivaTuner, doing a clean install of drivers, and using the PG278q monitor profile/driver from ASUS does NOT fix the back-light flickering problem with G-Sync.

I'm using a GTX780ti, but I will be testing it with a GTX680 just to be sure.

Repeating this method again since it seems to be a solid way to reproduce the issue:
Open up CS:GO
Press Shift+Tab and open up the web browser.
Go to a bright website (like nytimes.com)
Scroll up and down

It also was occurring at 90+fps. If the next driver update doesn't fix it, this monitor is going back. Something that cost $800 should not have these kinds of issues with its KEY feature.

UPDATE:
I reconnected my VG248QE w/ G-Sync module to try the same test. Lo and behold, the same issue happens on that screen too!

Same problem here. CS:GO with G-Sync is flickering. Without - it's fine. The thing is - the first few days I didn't see it, and then it start to manifesting more and more! Tried another DP cable - same propblems.

Intel i5 2500K, 8Gb RAM, ASUS Nvidia Geforce TITAN, WIn7x64.

Thanks guys for these posts! I am having the same problem and thought I was the only one!

Does anyone know if it's a driver issue or a panel issue? I can take mine back and swap it for another one. However if I'm just going to have the same problem I'd like to same myself the trip.

Currently turning off G-Sync has sorted the issue, but as others have said. Very hard to justify a $1,000 TN Panel without G-Sync

Sys Specs:

Intel 3960x
3-way SLI EVGA 780 Classified
16gb RAM
Both Windows Technical Preview and Window 8.1 tested.

Apparently, after reading the PCPer article and checking their referenced sources, yes there are users with flickering. Also other issues not related to gsync.

 

[JoeRambo]

Wow, i used to ignore such threads, because due to certain users things get overblown. But as owner of Swift i have to comment:

1) Yes there a tiny amount of flicker during loading screen when on gsync.
2) It takes a special game with special loading screen to actually notice. Out of the games I'm playing I have noticed it in Company of Heroes 2 - because you know in MP you load in several seconds and need to wait for others to load, all while staring @ 0FPS dark screen. So it is there, I've noticed it.

Is it a defect? Yeah, but way overblown due to beeing limited to load screens... That same Company Of Heroes 2 runs and looks amazing when in actual game.

 

[pleventi]

Yes, users actually notice this effect (without knowing to look for it). I just got my ROG Swift, and I saw this immediately upon loading Dota2. The main lobby screen exhibits this subtle flickering in the background grey; it is more pronounced at high brightness (out of box the monitor is at like 80% but really only needs 20% for proper output). It also shows up in Dragon Age; Inquisition load screens. Note: I have very sensitive eyes for refresh/flicker/etc.

Hopefully this issue can be fixed in-driver by Nvidia... you'd hope they can detect a stalled/static set of frames and artfiicially resend the previous frame or something like that. But worst case, its fine.

No other problems. I switched from an IPS 27" (Dell U2711), immediately noticed how much less vivid the colours were / washed out the screen was... but your memory fades quickly after not seeing them side by side. And gaming is incredible; looking around with the mouse in a FPS is incredible. Mouse accuracy in RTS games is so much better. And after callibration, the desktop graphics are fine.