200Hz Display review/questions

Talk about overclocking displays at a higher refresh rate. This includes QNIX, Catleap, Overlord Tempest, SEIKI displays, certain HDTVs, and other overclockable displays.

Re: 200Hz Display review/questions

Postby Spider-Waffle » 24 Oct 2015, 15:02

I don't question your knowledge, I just think I've been getting answers to a different but related and simpler question. Alright, I've gone and read most the complaints, and yes it seems a lot or most were over trying to run higher rates than firmware or EDID would allow, IE 1502 VT and 128hz or similar such things. That's all great and simple, no confusion there.

BUT, I've still read a lot of discussion over complaints of worse cross talk and/or strobing with CRU/VT mod and changing from a lower refresh rate, like 120hz to 128hz while CRU/VT is still plenty low enough for firmware and EDID to accept those refresh rates. And yes cables are mentioned often as a possible culprit citing that they are getting reasonably close to their limit.

So then that leads to me to 1920x1080 @ 200hz? http://www.csgnetwork.com/videosignalcalc.html
the bandwidth just seems very high compared lower bandwidths that were already grieving cables.
Spider-Waffle
 
Posts: 10
Joined: 19 Oct 2015, 13:01

Re: 200Hz Display review/questions

Postby AustinClark » 24 Oct 2015, 15:29

Spider-Waffle wrote:So then that leads to me to 1920x1080 @ 200hz? http://www.csgnetwork.com/videosignalcalc.html
the bandwidth just seems very high compared lower bandwidths that were already grieving cables.


The DVI cables that come with these overclockable 1080p monitors are quite thick and short. They're not really your typical DVI cable, and support bandwidths greater than the official spec would lead you to believe.
Even at 240Hz, bandwidth doesn't seem to be the limiting factor at 1080p.
AustinClark
 
Posts: 42
Joined: 14 Mar 2015, 00:03

Re: 200Hz Display review/questions

Postby Falkentyne » 24 Oct 2015, 15:59

Yes but you're mixing up different monitors here.
Just because the panel itself is identical between two monitors does not mean that the firmware is, even if the scaler is similar.
A panel may be physically capable of 200hz if the firmware allows it and the scaler can accept those timings.

VT tweaks have nothing to do with the Qinx panel here.

The Qinx panel uses LCD Reduced timings (1098 VT) for 144hz but there is no lock in the firmware so you can just push it all the way up to 200hz+ This seems to vary from panel to panel but you see what I'm getting at. You push it, it works until the panel or scaler just craps out with a white screen or sparkles start appearing.

Another panel (Xstar) managed 185hz with VT 1350. I don't know if that matters.

What we were talking about with the Benq is something completely different and not at all related to this topic.
The Benq seems to handle (strobing) based on scaler calculations. The scaler seems to calculate internal vertical (blank) by the VT value and the strobe phase is based on this. Changing VT causes internal scaler resolution to increase, which also decreases the amount of crosstalk on the physical (1080p) screen as the strobe is based on internal scaler resolution/Vblank.

Horizontal (HT) total doesn't seem to matter at all. All it does is increase or decrease pixel clock and must be at a certain lower limit depending on physical horizontal width, although there doesn't seem to be a "limit" for increasing it...just increases pixel clock.

VT seems to go in "steps" (range steps) and increase depending on range.
Default VT for 1920x1080@100hz is 1133.
1133 VT=scaler reports 1920x1080@100hz.
1125 VT=scaler reports 1400x1050@100hz.
1200-1260 VT=scaler reports bizarre resolution, forgot what. Vertical is above 1080, however. Monitor does not like this VT and shows out of range, display still shows image.
1340-1370 VT=scaler reports 1600x1280. VT 1354 works perfect on XL2720Z at 100hz. Vt 1350 causes frameskipping. did not test 120hz.
1370-1400 VT=scaler reports 1792x1344. Firmware does not like this signal, shows soft "out of range", as if you were trying to run 1024x768@85 or 1280x1024@85, display still shows image.
VT 1410-VT 1479=black screen (Out of range)
VT 1481-VT 1485=soft "Out of range", screen shows display anyway. Scaler resolution 1920x1440.
VT 1486-VT 1496=black screen out of range
VT 1497-VT 1502= scaler reports 1280x1440 ! Horizontal has decreased drastically. This seems to be what Lightboost uses internally.
Strobe crosstalk is reduced 25% over default VT. 1080->1440=25% increase in vertical resolution. VT 1133->VT 1500=25% increase in VT.
thus strobe crosstalk is reduced by 25% because its calculated on VT blank (scaler resolution).

Faint horizontal scanlines may appear around top/right when using VT 1497-1502 due to panel being pushed harder (VT blank? pixel clock? not sure why). Enabling Lightboost mode causes the same thing.

Monitor can accept 1497-1502 VT up to 128hz with normal timings. (if you get frameskipping change VT 1 higher or lower until it works).

Monitor can be "tricked" into downsampling a higher resolution through display scaling by using a VT range that will work for that resolution. 1920x1440, 1920x1200, 2560x1440 will all work if scaler is tricked into accepting VT range of 1497-1502.
2560x1440, 100hz refresh rate:
front porch 48, 3
Sync width 32, 5
Horizontal total: 2720
Vertical total: 1502
Works over DVI-DL (pixel clock patcher) and Displayport (6 bpc only).
OSD reports 2560x1440@60hz
Scaler reports 1280x1440 (remember the VT?)

2560x1440, 115hz (no artifacts). Displayport ONLY. DVI will "out of range" OOR error will flicker on and off.
HT: 2641
VT: 1497
No frameskipping.

2560x1440@120hz DP only: no frameskipping, but artifacts. Can't use; pixel clock is too high for scaler (artifacts are from hardware scaler limitation, according to ToastyX).

Monitor seems to accept 4k @ 30hz somehow (auto timings. 3840x2160@30hz auto).
3200x1800@60hz will black screen out of range
3200x1800@60hz will be accepted and shown valid image (OSD shows 1080@24p), scaler shows a bizarre resolution (like 2160x1620, I forgot. its really..bizarre) if you use VT for 3840x2160. This is 2220 VT. Use 2200 VT for 3200x1800@60 and monitor will work. Blur reduction is messed up. Monitor will double strobe if single strobe is "on" in service menu. Monitor will shut off backlight if single strobe is "off".


-------

This has nothing to do with the Qinx/Xstar 185-240hz overclocking. Benq firmware is hard locked to not exceed 145hz, doesn't matter what VT or cable you use.
Falkentyne
 
Posts: 2316
Joined: 26 Mar 2014, 07:23

Re: 200Hz Display review/questions

Postby AustinClark » 24 Oct 2015, 16:28

I have a question for Falkentyne and/or Q83Ia7ta

Would the problem we're having with the overclockable 1080p QNIX be explained by panel or scaler limitations?

Is it possible to implement overdrive ourselves, or is that something that needs to be engineered prior?

Lastly, do you think that pushing the scaler voltage up a tad would allow us to push the hardware a bit further? Even if you have to go slightly over spec.
AustinClark
 
Posts: 42
Joined: 14 Mar 2015, 00:03

Re: 200Hz Display review/questions

Postby Q83Ia7ta » 24 Oct 2015, 17:38

AustinClark wrote:Would the problem we're having with the overclockable 1080p QNIX be explained by panel or scaler limitations?
If problem is "going to white" I guess it's scaler related. If problem is "a bit of picture degradation" I guess it's more panel related or power circuit.
AustinClark wrote:Is it possible to implement overdrive ourselves, or is that something that needs to be engineered prior?
For me it's rocket science :)

AustinClark wrote:Lastly, do you think that pushing the scaler voltage up a tad would allow us to push the hardware a bit further? Even if you have to go slightly over spec.
dunno
Q83Ia7ta
 
Posts: 587
Joined: 18 Dec 2013, 09:29

Re: 200Hz Display review/questions

Postby dhaine » 25 Oct 2015, 00:41

dhaine wrote:a question for the expert, it seems this monitor does not have any overdrive ? does having a monitor with such high hz can make input lag faster than a screen at 120/144 with overdrive (when a game actually achieve 300+fps)?

any comments about this ? :)
dhaine
 
Posts: 34
Joined: 22 Nov 2014, 00:25

Re: 200Hz Display review/questions

Postby MrBrown » 25 Oct 2015, 09:47

So this monitor doesnt have overdrive, is that correct? Thats a bummer, because overdrive on Benq monitors improves the response time by 2x or even a little higher.

For example the XL2430T has these response times without overdrive. The 144hz compares like this:

Image

Image

Thats 10,6ms average response time, down to 3ms, which is around 3x better.

Because of that, unfortunately, Im not gonna get the monitor. The motion blur will be just too high without overdrive and without any blur reduction..
Falkentynes BenQ Service Menu thread: viewtopic.php?f=2&t=2467
MrBrown
 
Posts: 38
Joined: 05 Feb 2014, 08:06

Re: 200Hz Display review/questions

Postby Q83Ia7ta » 25 Oct 2015, 10:16

There is overdrive but it's quality is a bit lower than from benqs.
It's 1 or 1.5 gtg ms (depends on model) ofc overdrive used.
Q83Ia7ta
 
Posts: 587
Joined: 18 Dec 2013, 09:29

Re: 200Hz Display review/questions

Postby MrBrown » 25 Oct 2015, 11:01

Ok I see. Can someone please test if you can connect a PS4 or Xbox One to this monitor using a HDMI-->DVI cable? Which are essentially 1080p Devices @ 60Hz.

Also how many ppl were able to overclock this monitor to 240hz? Id only consider buying it if the chances are good to hit 200+ hz in overclock, because I dont think that the difference between 144hz monitors to 185-190hz or so is noticable enough.
Falkentynes BenQ Service Menu thread: viewtopic.php?f=2&t=2467
MrBrown
 
Posts: 38
Joined: 05 Feb 2014, 08:06

Re: 200Hz Display review/questions

Postby Comanglia » 25 Oct 2015, 12:00

MrBrown wrote:Ok I see. Can someone please test if you can connect a PS4 or Xbox One to this monitor using a HDMI-->DVI cable? Which are essentially 1080p Devices @ 60Hz.

Also how many ppl were able to overclock this monitor to 240hz? Id only consider buying it if the chances are good to hit 200+ hz in overclock, because I dont think that the difference between 144hz monitors to 185-190hz or so is noticable enough.


You'd probably be wanting to try 192Hz just so you have a higher refresh divisible by 24.

You could connect devices like a PS4 or Xbox one via an adapter but I'm 100% sure you can't get the overclock to work doing so.

as far as I know 3 people have hit 200Hz or higher on this panel, I've only heard of 4 people trying though.

Now as to each specific question/statement

"Also how many ppl were able to overclock this monitor to 240hz?"
Just because we can hit it doesn't mean it's stable given the current information, I'm trying out some work arounds but I'm waiting on some equipment.

"Id only consider buying it if the chances are good to hit 200+ hz in overclock"
200Hz flat is pretty damn stable, just the Color is really hard to make it look right at this point due to no OSD menu.

"because I dont think that the difference between 144hz monitors to 185-190hz or so is noticable enough."
If you're used to playing games competitively and have extremely high FPS you'll notice a slight difference at 168Hz, getting better at 192Hz, and I'll say 240Hz is obvious in it's difference but the chances of your screen just going solid white are just to high to be used.

Just fyi the difference between 144Hz and 200Hz is about as big as going from 60Hz to 72Hz in terms of input lag, but something that's harder to quantify is the feeling of movement in game when doing large "twitch" shots. Which is much more profound.

-edit-
at 144Hz or lower this monitor might have better colors than other common 144Hz TN panels. QNIX is marketing this as a true 8bit display rather than a 6bit+dithering. I haven't checked into this much but would be pretty cool if that was the case.
Comanglia
 
Posts: 38
Joined: 13 Oct 2014, 16:06

PreviousNext

Return to Display Overclocking

Who is online

Users browsing this forum: No registered users and 2 guests