Benq XL2411Z + VT1502, random black screens issue

[Power78]

Hello everybody,

I have a Benq XL2411Z with v4 firmware since 2 weeks ago.
I have a custom resolution 1080p,120Hz,VT1502, Blur reduction ON.
I use the XL2420Z icc profile, and 75% vibrancy on the nvidia control panel.
CG : GTX 670.
I use the BB strobe utility with 1.2 persistence, 0 crosstalk (earliest).

Now my issue : I often encounter random black screen(screen going to sleep, orange power led) on google chrome for 2 to 6 seconds when surfing.
I also noticed that too white pages (http://www.julienlevesque.net/pertinence.jpg, triggers 90% of the time) or https://twitter.com/BenQGaming(after clicking the top right "tweet" button, 75% of the time) seems to trigger it undefinitely (I have to close the page or change the resolution to a non custom one for the screen to come back from sleep).
It also occured twice when playing CS:GO when I got full flashed.

I'm pretty sure it's coming from the custom resolution (specially the VT tweak) since with a non custom resolution it doesn't occur, and with a custom with VT1350 it doesn't occur too, but I'm wondering what is the issue, and if my screen could be defective.
It also does not occurs if Blur reduction is OFF.

I can provide all the required informations, hopping somebody knows what is happening to my screen .

Thank you for your help.

[Falkentyne]

Try changing the VT to 1500, VT 1499 or 1497 (1497 is the lowest in this lightboost compatible range (accelerated scanout; lightboost uses this area internally but from a much lower VT).

All of these VT's do the same thing, so you can use any range in 1497-1502, whichever one does not cause frameskips. They send a 1440 vertical resolution signal to the scaler (which is why the VT works, the strobe is calculating 1440 vertical lines instead of 1080, but the physical screen is 1080, if that makes sense). Just some cause strobe errors and some don't (e.g. Vt 1502 at 120hz on XL2720Z causes random frameskipping on resolution switch or monitor profile /preset changes, VT 1500 and VT 1499 do not).
At 85hz for example, all VT's (1497-1502) cause frameskipping except VT 1501, which is perfect.

On XL2720Z, VT 1350 (at 100hz, I didn't test 120hz) is unstable. always frameskips 100% of the time. VT 1354 is perfect every time.

(the frameskipping tests I mentioned have nothing to do with strobing (BBR/benq blur reduction) off or on...happens with BBR off too, just a lot harder to notice with BBR off. it's just the scaler not liking the VT value).

Anyway, report back.

BTW Are you 100% sure that this does NOT happen if blur reduction is off?
I mean if you are using the VT tweak but have blur reduction off, are you 100% certain of this?
Because monitor going into power save mode is usually video card loss of signal...blur reduction should not cause this as the video card doesn't care about strobe off or on...

Also do me a favor too.
Set persistence to 5.0ms
Does it happen at 5.0ms?

Then set persistence to 0.167ms.
You can't do this in blur busters utility. You need to use service menu and set strobe duty to 001. (windows utility wont go lower than 003).

service and factory menu codes are here.

http://forums.blurbusters.com/viewtopic.php?f=2&t=2467

One last thing.
Disable your ICC profile and disable the NVidia digital vibrance or set it to default.
Then use OSD color settings 100R, 98G, 96B, 100 brightness, contrast 50.

Report back please. Make sure you are thorough with your findings. You could have a badly calibrated backlight or maybe found a bug. Nvidia CP sends digital calibration signals to the monitor (which is why the VGA color gain and color offset in the factory menu only work in VGA dsub mode; the video card drivers control this digitally for DVI/DP/HDMI).

[Power78]

Ok I tested everything like you said :
I found a page where I had the issue 100% of the time so I could reproduce at will.
Digital vibrancy at 50%, icc profile as default for all the tests.

Black screen when loading the page (loading www.addic7ed.com from www.reddit.com) (on ~~ 50-70 tests) :

VT 1502 : 100% of the time
VT 1501 : 100%
VT 1500 : 100%
VT 1499 : 100%
VT 1498 : 75%
VT 1497 : 0%
VT 1350 : 0%

Also you were right, it also happens with MBR off !

Persistance had no impact on the black screen appearance, 5.0 ms or 0.167 ms (001)

I also noticed that I have a strange vertical green "artifact"(http://imgur.com/w2irJMu) on this page when I use the VT tweak in the 1497-1502 range, but not on 1350 or untweaked resolutions.

I will keep 1497 for the moment since I do not have the issue with it, but if you have clues of what causing the blacks screens, it would be awesome

[Falkentyne]

What page is that imgur link from?

Sounds like you have a bad panel. If possible, I would RMA it.
I would not be happy if I had that issue.

Since you have an Nvidia card, can you use the INF override and activate 3d vision 2 (From the Nvidia CP setup) and install the lightboost modes?
They only have to be unlocked once with the 3d vision 2 test+inf override (but every time the monitor is unplugged from the wall, it has to done again). The lightboost INF how to is on the front page. it's easy since you have an NVidia card.

Once lightboost mode is activated by the test, you can enable it manually by using the following timings:
100 hz: VT 1138
120 hz: VT 1149.

Once you're in 3d mode, test those page and see if you get the same issue.

*edit* Masterotaku has the same monitor and he said the problem does not happen to him at those settings. You should RMA for sure.
I'm curious if this happens in lightboost mode, especially the green line thing you got on the imgur test (what website was that anyway?)
Because lightboost pushes the panel even harder than benq blur reduction with VT tweak does.