BenQ XL2720Z overclocked to 220Hz and 250Hz [SUCCESS!]

Talk about overclocking displays at a higher refresh rate. This includes homebrew, 165Hz, QNIX, Catleap, Overlord Tempest, SEIKI displays, certain HDTVs, and other overclockable displays.
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CubanLegend
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Re: BenQ XL2720Z overclocked to 220Hz and 250Hz [SUCCESS!]

Post by CubanLegend » 03 Dec 2020, 03:13

Chief Blur Buster wrote:
19 May 2019, 18:31
WARNING: Be careful mixing 220Hz + Blur Reduction on older firmwares
Strobe Pulse Width (Persistence) above approximately 10 during a 220Hz overclock may cause the monitor to excessively overvoltage to backlight.

If you use Strobe Utility, configure Persistence to 5 before you overclock
I accidentally did, and caused the monitor to go bright and crash (it wouldn't turn back on again until I unplugged and connected HDMI first, turned off Blur Reduction, then plugged back in the DisplayPort); the XL2720Z uses a voltage-boosted strobe backlight. If you overclock the XL2720Z, be very careful using Blur Reduction mode. The voltage boosting is even more powerful at 220Hz, which means it could potentially cause Blur Reduction to burn out the backlight/electronics. So be careful... If you've ever done Strobe Utility tweaking before, launch it first at 144Hz, slide Persistence all the way down to around 5, and exist before you overclock your XL2720Z. Newer firmware will prevent too much voltage boosting, but the older firmwares didn't.

220Hz is low-risk if you don't use Blur Reduction
That said, 220Hz without blur reduction should be pretty harmless. Panel overclocking is generally harmless the am, but it is generating a potential risky bug with the Blur Reduction mode (at least with earlier firmware versions that doesn't have a protected voltage-boost).


I tested V2 firmware too, the 220Hz overclock works all the way back to V2.

Continuing more tests.
So I'm on V2 and I managed to get 220hz with Persistence set to 5 ag 144 hz before goint to 220hz, for my 220hz Resolution I have porches set to 1 on both.. Yes its set to YcBR422 to the reds are picelated.. but the smoothness is amazing and this will be my daily driver setting! Also I'm running the OoRBuster.exe that i found on this forum.. Thank you!

I will try to update my firmware to v4 to see if i can reach 240hz! :D (as of right now testing anything above 220 doesnt work)

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CubanLegend
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Re: BenQ XL2720Z overclocked to 220Hz and 250Hz [SUCCESS!]

Post by CubanLegend » 10 Dec 2020, 01:26

So thanks to this thread i managed to get a 240hz 1920x1080p resolution set up and stable!
Horizontal Vertical
FP:32 3
SW:24 1
BP:8 10
BL:64 14
VT:1984 1094
loopy750 wrote:
03 Feb 2020, 09:08
Wow 280Hz, very nice. I'm a little confused reading that.. sounds like there's a little more to it than simply setting a preset. Also I wonder if it would work for XL2720Z. I do have my XL2720Z pushed to the (known) limit of 250Hz which I have been using for a while (after deciding to push more than 220Hz). When limiting the game engine FPS from 144 to 250 FPS, there is a noticeable difference, so it's a nice step up. The image quality and colour is definitely not something I'd recommend for desktop use, only for FPS games:


250Hz.png
AMAZING! I was able to get 240hz with my own timings i mentioned .. but now im able to do 250hz with these timings! ABSOLUTELY AMAZING.. so is there any monitor better than these XL2720Z's that can 60hz single strobe too? i mean the single strobe range has been seen from 60hz to 250hz in native 1920x1080p, that is insane..
Falkentyne wrote:
21 May 2019, 01:45
Chief Blur Buster wrote:Did some more research.

OK,
- I found out the NVIDIA drivers, is indeed, using 6bpc. You're right on that count.
- BUT my current NVIDIA drivers is apparently doing GPU-side temporal dithering. Neat. GPU-side FRC!

Today I learned, temporal dithering is a feature of NVIDIA graphics drivers, permanently turned on by default on Windows systems. This is a little-known feature that NVIDIA graphics drivers already is doing an FRC equivalent. There's even a little known hack to disable NVIDIA temporal dithering. Nontheless, this explains why I'm seeing 8-bit color depth with 6bpc output.

Perhaps NVIDIA is better than AMD GPU-side FRC. These TN panel is 6bit anyway. So in an ideal world -- in theory -- it doesn't matter if the monitor-side FRC or GPU-side FRC as long as the dithering quality is nearly identical! Metaphorically, it's akin to GPU scaling versus monitor scaling. They can be well on either side. So it theoretically doesn't matter WHO does 6bpc->8bpc, as long as the job's being done well. Nontheless, the monitor-side FRC might be slightly superior, but:

The bigger problem is the calibration. I improved my color calibration further.
I think I got the game looking almost as good at 220Hz as 144Hz, when I do this:

BetterPicture.png
BetterPicture.png (17.13 KiB) Viewed 1 time


In Entech Taiwan SoftMCCS,
1. FIRST, click "Standard/default" below "Display application - 0xDC"
2. SECOND, click "DIsplay application - 0xDC --> ACTIVATE"
3. THIRD, slide sharpness carefully to 5
4. FOURTH, set all red/green/blue gains to 100
5. FIFTH, select "6500K" radio button

Now the 220Hz colors look much better in my video games. Not as good as 144Hz but much, much better now.
It certainly now looks 8bit color depth in my games.
Well I found out how to get 165hz working.
The timings posted cause frameskipping every 2 seconds.
I had to use these settings:

HT: 2005
VT: 1088
165hz

This kept pixel clock at 359.94 mhz and 8 bit color, and there was no frameskipping. 8 bpc stops Overwatch from becoming horribly banded. I think overwatch uses some strange blending on the walls as I've never seen banding that bad in any game before at 6 bpc.

At the other settings that were posted in the OP, it frameskipped -all- the time no matter how many times I pressed the S-switch. I know at strange VT's I had to use to keep 120hz under 360 mhz pixel clock and 125hz (impossible to run at 8 bpc), sometimes I had to do the S-switch to stop frameskipping(which was always very obvious, not that 2 second tick), until I found VT's that worked all the time (like 85hz, VT 1501)..

Blur reduction is next to unusable, though. Crosstalk is ........just........half the screen, literally. Might be very good for people who don't use blur reduction however. I haven't tried using the OSD to toggle AMA for blur reduction off, assuming I can even enter the OSD (haven't tried yet, because crosstalk is horrible).

Anyway I think those timings should be added to the OP just in case. Because I can't be the only person who is going to try 165hz and get 2 second stutters. And maybe AMD does things differently than Nvidia also so I don't know.

I wanted to get an XL2740 to play with but can't afford it. And now with that strobed freesync monitor coming out...and the XL2740 not capable of 60hz blur reduction (single strobed), well... :/
Thanks so much for the stutter free 165hz on My XL2720z, thank you! :)

Falkentyne
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Re: BenQ XL2720Z overclocked to 220Hz and 250Hz [SUCCESS!]

Post by Falkentyne » 10 Dec 2020, 02:03

I think those were on the AMD video card, right?
My RTX 3090 FE stutters at those timings :(
I had to use other timings.

1920, 1080
24, 3
32, 5
4, 6
60, 14
HT: 1980, VT: 1094
Refresh: 165.000 hz
horizontal: 180.510 khz
Pixel clock: 357.41 mhz

These were the only timings I could get 165hz to never stutter on my 3090 and to maintain RGB instead of it stepping down to ycbcr422.
(seems like the 359.94 mhz cutoff on AMD is much lower on Nvidia).

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CubanLegend
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Re: BenQ XL2720Z overclocked to 220Hz and 250Hz [SUCCESS!]

Post by CubanLegend » 10 Dec 2020, 15:14

Falkentyne wrote:
10 Dec 2020, 02:03
I think those were on the AMD video card, right?
My RTX 3090 FE stutters at those timings :(
I had to use other timings.

1920, 1080
24, 3
32, 5
4, 6
60, 14
HT: 1980, VT: 1094
Refresh: 165.000 hz
horizontal: 180.510 khz
Pixel clock: 357.41 mhz

These were the only timings I could get 165hz to never stutter on my 3090 and to maintain RGB instead of it stepping down to ycbcr422.
(seems like the 359.94 mhz cutoff on AMD is much lower on Nvidia).
Thanks a lot for the clarification.. i wasn't aware those "HT: 2005 VT: 1088 165hz" timings were to avoid stuttering on AMD.. I seemed to have avoided stuttering on my GTX1080 with that resolution though.. so I'll compare it to the timings you just posted above. I'll report back with results..

By the way.. why is 360MHz the RGB 444 Cutoff on these BenQ Monitors? I'm curious, i've see other monitors do higher resolutions and refresh rates while maintaining RGB.. is it the scaler or the on board electronics that's limited to that MHz for producing RGB444 before stepping down to yCbCr422?

Falkentyne
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Re: BenQ XL2720Z overclocked to 220Hz and 250Hz [SUCCESS!]

Post by Falkentyne » 11 Dec 2020, 21:08

CubanLegend wrote:
10 Dec 2020, 15:14
Falkentyne wrote:
10 Dec 2020, 02:03
I think those were on the AMD video card, right?
My RTX 3090 FE stutters at those timings :(
I had to use other timings.

1920, 1080
24, 3
32, 5
4, 6
60, 14
HT: 1980, VT: 1094
Refresh: 165.000 hz
horizontal: 180.510 khz
Pixel clock: 357.41 mhz

These were the only timings I could get 165hz to never stutter on my 3090 and to maintain RGB instead of it stepping down to ycbcr422.
(seems like the 359.94 mhz cutoff on AMD is much lower on Nvidia).
Thanks a lot for the clarification.. i wasn't aware those "HT: 2005 VT: 1088 165hz" timings were to avoid stuttering on AMD.. I seemed to have avoided stuttering on my GTX1080 with that resolution though.. so I'll compare it to the timings you just posted above. I'll report back with results..

By the way.. why is 360MHz the RGB 444 Cutoff on these BenQ Monitors? I'm curious, i've see other monitors do higher resolutions and refresh rates while maintaining RGB.. is it the scaler or the on board electronics that's limited to that MHz for producing RGB444 before stepping down to yCbCr422?
Displayport limitation. These older Benq monitors are basically DP 1.1 monitors. While it says "DP 1.2", it doesn't support High Bit Rate 2 (HBR2) which is required for DP 1.2 compliance, which means it falls back to 6 bpc at 360 mhz, or YCbCR422 (at somewhere between 357-359 mhz), and is limited to 480 mhz under that mode (going higher may make the refresh rate not even appear as a selectable option, but it seems that some people managed to get it higher than 480 mhz).

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CubanLegend
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Re: BenQ XL2720Z overclocked to 220Hz and 250Hz [SUCCESS!]

Post by CubanLegend » 11 Dec 2020, 21:14

Ah, understood about the DP limitation, i just started reading into those and their pixel clock limits for 1.1 1.2 and 1.3, interesting stuff.

Also your 165hz timing worked perfectly! thank you!

I also used your 250hz timing and 240hz timings sucessfully for a proper 1080p 240hz and 250hz refresh rate in CRU. :) This monitor is amazaing.. has any other monitor been released with single strobe from 60-250hz since this one?

Ozzuneoj
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Joined: 13 Oct 2016, 13:35

Re: BenQ XL2720Z overclocked to 220Hz and 250Hz [SUCCESS!]

Post by Ozzuneoj » 10 Feb 2022, 14:37

Is anyone using an nvidia card with the XL2720Z? I have had a GTX 970 and a 3060 Ti and neither will allow me to get full RGB 8bpc with anything over ~340Mhz pixel clock using DisplayPort. It has been this way through multiple builds with this GPUs, multiple operating systems, multiple DP cables, etc. for the past 5 years I've had this monitor.

If I do the custom resolutions that approach but don't exceed 359.99Mhz using the nvidia control panel it will leave the color mode as RGB but drop to 6bpc (and disable DSR, which I want to use).

If I do it through CRU it will keep 8bpc but it will switch to yCbCr422, which destroys text and image clarity.

Falkentyne
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Joined: 26 Mar 2014, 07:23

Re: BenQ XL2720Z overclocked to 220Hz and 250Hz [SUCCESS!]

Post by Falkentyne » 14 Feb 2022, 16:57

I replied to your post in the benq thread.

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