Question to BenQ XL2720T users

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shreebles
Posts: 6
Joined: 13 Jul 2015, 10:48

Question to BenQ XL2720T users

Post by shreebles » 13 Jul 2015, 11:03

Hello all,
I've been mostly a lurker up to now, and found lots of interesting research and articles here.
I used the BenQ XL2420T for some time and I'm quite happy with it, but sometimes I wish for a larger screen. I have two monitors now but it's just too much clutter so I a wanted a single bigger screen, so I found a XL2720T for quite cheap: 280€, a refurb model with some scratches on the case. I hope to get it soon but I'm a bit worried that it might not support the custom resolutions that I heavily depend on.

TLDR; Could someone who has the XL2720T and an Nvidia graphics card test the following resolutions for me?
(Nvidia Control Panel > Change resolution > Customize > Enable resolutions not exposed by the display > Create custom resolution)

Code: Select all

-Horizontal: 1920
-Vertical: 1440
-Refresh rate: >100hz (120 ideally)
-Color depth: 32
-Scan Type: Progressive
-Timing: Automatic

Code: Select all

-Horizontal: 1440
-Vertical: 1080
-Refresh rate: >100hz (120 ideally)
-Color depth: 32
-Scan Type: Progressive
-Timing: Automatic
It would help a lot because if it doesn't support either of these I'll have to send it back.
The XL2420t has been lovely in that regard, I use it @ 129hz with the first and @ 144hz with the second resolution.

For those of you who play CS:GO - give that first resolution a spin if you like playing 4:3. It's like regular 4:3 stretched, but in HD! :mrgreen:

Hope someone can help!
Thanks in advance!
shreebles

Falkentyne
Posts: 2795
Joined: 26 Mar 2014, 07:23

Re: Question to BenQ XL2720T users

Post by Falkentyne » 13 Jul 2015, 18:24

The first resolution doesn't even work. It exceeds the physical size of the panel. How exactly did you get such a resolution to work?
Not to mention the physical size being exceeded, but if I try to even enter this in CRU, in manual resolution, it puts a Vertical total of 1485. I did not test this though.

The second is a common custom 4:3 resolution that fits at 1080p (I actually have that myself).

*EDIT*
Ok I did test this, but on an XL2720Z. The XL2720T uses the same Mstar scaler as all of Benq's XL series 1080P monitors (Mstar 8556T), the Z series also use this scaler, so I figured I might get a valid image.

Manual resolution 1920x1440@100 hz (I did not test 120hz...pixel clock is 390 MHz!)
I get an image on the screen that looks like a downsampled higher resolution but the OSD shows "Out of range!"
I can close the out of range popup by selecting displayport again but that's it. I lose all OSD control, but the computer is usable.

(black screen out of range errors, which are "hard" errors, prevent you from closing the out of range popup, e.g. trying to create a 2560x1440 resolution, or using a 1503 or higher Vertical Total, etc).

On my AMD 290x videocard, when I created 1920x1440, it also automatically added a 1920x1200 resolution too. This also gave a valid image but the "Out of range" error popup.

I used an XL2720Z for this.
Your XL2720T most likely uses very similar hardware scaler code as the XL2420T, as they all came from the same generation, despite the panels being different sizes, they're still 1080p.

Your resolution will work, but will probably show the out of range error also.

Why do you want such a resolution, anyway? What's the point of this? The aspect settings are incorrect. 1440x1080 with 1:1 or "Aspect" set in the OSD (or in windows, if GPU scaled) will have correct pixel mapping, but I don't see the point of 1920x1440. I'm guessing you want more image data, since 1440x1080 stretched to fullscreen will look bad on 1920x1080, and 1:1 will have black bars horizontally, but you can't use 1:1 on a resolution that is higher than what the monitor supports.

I really don't see the point...
If it's such a big deal, use Virtual super resolution (AMD) or Dynamic super resolution (Nvidia) or whatever it's called on Nvidia cards. DSR). You'll be doing the same thing anyway, but without having to deal with losing OSD control with OOR errors.

*edit 2*
1920x1440@120hz either gives swimming pixels with an out of range error (that can be closed, as before, but those swimming pixels can't be good for the monitor) or a hard out of range error which can not be closed (black screen, no display). Seems to be random, but either way I'm way out of specification anyway. Might work with a lower horizontal total and porch/sync widths (probably won't stop the "soft" out of range error though).

I think the Nvidia custom resolution panel defaults to front porch (48,3), sync width (32,5), and Horizontal total 2080, which will have a lower pixel clock than what AMD defaults to (it defaults to the normal standard of front porch (88,4), sync width (44,5), and Horizontal total 2200. Not going to test this further. But I think I can safely say it will work on your 2720T. But I ask again, why?

If you really want this, use Nvidia DSR.

shreebles
Posts: 6
Joined: 13 Jul 2015, 10:48

Re: Question to BenQ XL2720T users

Post by shreebles » 14 Jul 2015, 06:14

Hi Falkentyne,
First of all thanks for testing this.

Secondly, I understand this confuses you as I did not think it would be possible myself. But it does work.
The display seems to scale down those extra pixels to fit into the 1080 vertical ones it has. I can assure you it has worked perfectly for several months now, at 129hz.

Your other question was why and I think I hinted at the reason in my first post. I play a lot of Counter-Strike and a lot of people play 4:3 resolutions, either with black bars (because it looks like their old 4:3 CRT) or 4:3 stretched on a 16:9 display.
Stretched makes sense in CS because it makes everything look a bit "zoomed in". You lose some peripheral vision but CS is a very passive game, where you often have to watch a single angle on the map for a long time. Everything that is narrow on a 16:9 resolution gets wider on a 4:3 stretch resolution: Very small gaps where enemies cross, doorways, windows, an enemies head...
Especially that last one can be crucial in a game where a headshot is often an instant kill and can decide the round for your team.

After trying it out I got used to this very quickly. I don't like to sit closer to the screen than I already do, but feel at 16:9 everything is just too small especially when the enemy is far away. So I used the highest 4:3 stretched resolution available to me - 1280x960.
On a FHD monitor this makes everything look like ass of course. But for me it was more important to see everything well, rather than enjoy how good the game looks (hint: not that good to begin with).

Then I saw a post about custom resolutions, people suggested adding 1440x1080 manually. Much better of course, but I wanted to see what else was possible with this panel. So I just multiplied 1920 by 0,75 (to get a 4:3 resolution) and got 1440. To my great surprise this resolution works, though not with the full 144hz. But I'm happy with 129. It looks a lot better and sharper than 1440x1080.

I fear the 2720T might have issues doing this resolution at over 100hz. Since you have the 144hz model and it's struggling with that. I'm fine with 120 or so but drop under 100 and the point of buying such a fast display starts to fade away.

I am happy to give DSR a try, but does it support custom resolutions? Now that you understand that my goal really is running the display at the wrong aspect ratio (4:3, stretched to 16:9), do you still think it would be a good option?

Falkentyne
Posts: 2795
Joined: 26 Mar 2014, 07:23

Re: Question to BenQ XL2720T users

Post by Falkentyne » 14 Jul 2015, 06:34

I don't think VSR or DSR works with custom resolutions that are using wrong timings, but I think it can upsample lower resolutions that are using default timings.

For example, if I enable VSR, and my 1920x1080@100hz resolution is using default timings, I can do 2560x1440 @ 100hz, however if I have a custom vertical total (thus a custom resolution) for improving the blur reduction crosstalk @ 100hz, then 2560x1440 is limited to 60hz.

The closest resolution VSR that is added that matches 1920x1440 is 1800x1440.
This resolution is apparently 1440x1080 upsampled, because I have a 1440x1080 @ 120hz custom resolution defined. When I enable VSR and select 1800x1440, the monitor OSD thinks it's 1440x1080.

So you can try your 1440x1080, enable DSR and see if you get something similar to 1800x1440.

When you enter 1920x1440@100hz in your 2420T, you don't get an out of range warning on your OSD?

shreebles
Posts: 6
Joined: 13 Jul 2015, 10:48

Re: Question to BenQ XL2720T users

Post by shreebles » 14 Jul 2015, 07:13

Quick reply, I'm at work.
Falkentyne wrote: When you enter 1920x1440@100hz in your 2420T, you don't get an out of range warning on your OSD?
I can enter 1920x1440@100hz, or 120hz without the warning. Starting from 130hz, and higher, I get the warning. So I use 129hz.

PS:
Falkentyne wrote: So you can try your 1440x1080, enable DSR and see if you get something similar to 1800x1440.
I'll test that tonight, thanks!

Falkentyne
Posts: 2795
Joined: 26 Mar 2014, 07:23

Re: Question to BenQ XL2720T users

Post by Falkentyne » 14 Jul 2015, 09:28

Ok I was able to create it successfully, without the error. This was at 100hz.
The monitor OSD idenfies it as 1920x1440@60, not 100, though. But it's 100.

I'm having a "swimming pixels" issue at 120hz, but I don't know exactly why. I have a custom 1920x1080@125 hz resolution with a 1498 vertical total and 389 MHz pixel clock that looks just fine, yet 1920x1080@120hz with 396 MHz pixel clock and Vertical total 1500 (horizontal total 2200) has swimming pixels while, Horizontal total 2080 / VT 1500 (374.40 MHz pixel clock) doesn't. Yet the 1920x1440@120hz has a lower pixel clock than my 125hz yet has even worse swimming pixels than the "bad" 120hz one (2200 HT)...w.e. I'll figure it out later.

Anyway....

I had to use a 1502 vertical total after using LCD automatic timings for 1920x1440 (First I had to enter the resolution under LCD automatic, save it, but this would give the black screen out of range hard error, as the Vertical total was 1510). Then I edited it, lowered the VT to 1502, saved, restarted the driver, and it worked.

This doesn't seem to work with manual timings directly.
Using manual timings makes it use a Vertical total of 1485. This VT gives the out of range error even if you use it on an existing resolution like 1920x1080. Yet automatic timings made it use 1510, which is past the monitor's hardware limit of VT 1502.

Can you check your resolution and edit it and look for what the "Vertical Total" is? If The Nvidia control panel won't show you (it should, though, ToastyX CRU should show you).

I had no idea that the older T series responded to vertical totals, since the vertical total changes on the blur reduction Z series are for reducing the strobing crosstalk.

I'd love to try this new resolution in games, but I can't...the strobe crosstalk is too high. I'm assuming even though the vertical total is higher (1502 instead of 1125 default) which should massively lower the strobe crosstalk at the bottom of the screen, this is literally "un-done" by the 1440 vertical pixel size (which basically is ilke running 1920x1080 with a 1125 VT, default (this has to do with benq blur reduction). I use blur reduction all the time and there's too much crosstalk with 1920x1440@VT 1502, while 1920@1080@ VT 1502 looks great at 100hz.

Anyway you have the answer you're looking for.
But tell me: why get an XL2720T?

Get the XL2720Z and enjoy benq blur reduction!
(You can always turn it OFF if you don't want it and you still have all the capabilities of the XL2720T).

shreebles
Posts: 6
Joined: 13 Jul 2015, 10:48

Re: Question to BenQ XL2720T users

Post by shreebles » 15 Jul 2015, 06:13

Falkentyne wrote:Ok I was able to create it successfully, without the error. This was at 100hz.
The monitor OSD idenfies it as 1920x1440@60, not 100, though. But it's 100.
That sounds great! Seems like mine could get here in an hour or two. I shall test!
Falkentyne wrote:I had to use a 1502 vertical total after using LCD automatic timings for 1920x1440 (First I had to enter the resolution under LCD automatic, save it, but this would give the black screen out of range hard error, as the Vertical total was 1510). Then I edited it, lowered the VT to 1502, saved, restarted the driver, and it worked.

This doesn't seem to work with manual timings directly.
Using manual timings makes it use a Vertical total of 1485. This VT gives the out of range error even if you use it on an existing resolution like 1920x1080. Yet automatic timings made it use 1510, which is past the monitor's hardware limit of VT 1502.
Weird, could it be driver dependant? I never had a problem using automatic timings with my setup.
Falkentyne wrote: Can you check your resolution and edit it and look for what the "Vertical Total" is?
Here's everything:
resolution.PNG
resolution.PNG (23.99 KiB) Viewed 7921 times
Falkentyne wrote: I had no idea that the older T series responded to vertical totals, since the vertical total changes on the blur reduction Z series are for reducing the strobing crosstalk.

I'd love to try this new resolution in games, but I can't...the strobe crosstalk is too high. I'm assuming even though the vertical total is higher (1502 instead of 1125 default) which should massively lower the strobe crosstalk at the bottom of the screen, this is literally "un-done" by the 1440 vertical pixel size (which basically is ilke running 1920x1080 with a 1125 VT, default (this has to do with benq blur reduction). I use blur reduction all the time and there's too much crosstalk with 1920x1440@VT 1502, while 1920@1080@ VT 1502 looks great at 100hz.
Wow, I could never use blur reduction. I actually buy the BenQs because they are fast, I like the gaming settings, and because they don't use PWM. I don't want any flicker ever no matter what brightness is set.
I tried BR with ToastyX Utility, but playing for more than 10 minutes makes me dizzy. I can not see the strobes but I can 'feel' them if you know what I mean. My eyes feel so different, then. I cannot see a benefit compared to the regular 144 or even 120hz image. Meanwhile, the difference between 60 and 120hz seems positively gigantic.
Also, the image is too dark for me, and dark equalizer doesn't work anymore.
I always have the lights on in my room so I often use 100 brightness when gaming. When surfing the web, I use between 30 and 50. I would have to play in the dark to get adequate brightness with blur reduction.
Falkentyne wrote: Anyway you have the answer you're looking for.
But tell me: why get an XL2720T?

Get the XL2720Z and enjoy benq blur reduction!
(You can always turn it OFF if you don't want it and you still have all the capabilities of the XL2720T).
Yes, that's a lot of answers, thanks for your help!
In my initial post I mentioned the reason for getting the 2720T in the initial post: The price.
I have two monitors here at the moment and I wanted to sell both to pay for the new BenQ. Like I said I don't use blur reduction, so the benefit for me would be 144hz capability. Then again I've been playing with 129 or even 120hz for a while and it's only a minor difference for me.

To put the price into perspective:
I got the 2720T for 280€, used, scratched case but no scratches on the screen and no dead pixels.

The 2720Z, used starts at 290 (scratches on the screen!) or 365 (1 dead pixel). These weren't options for me so the cheapest I could get was 400€, used, scratches on the case.

That's quite a difference, but I might have to go that route should my 2720T turn out to be unable to work with my desired resolution at >100hz.

Falkentyne
Posts: 2795
Joined: 26 Mar 2014, 07:23

Re: Question to BenQ XL2720T users

Post by Falkentyne » 15 Jul 2015, 07:03

Probably because you're using the Nvidia control panel to create resolutions. Nvidia CP not only creates them at slightly different timings (e.g. 2080 horizontal total instead of 2200) but you can also test a new resolution on the fly before saving it, which you can't do with ToastyX's CRU (since that's a third party program, rather than part of the Nvidia drivers). You can create some custom resolutions with AMD, but the functionality is VERY VERY limited through the CCC.

I can't create that resolution with those timings in ToastyX CRU.
I can get the pixel clock and kHz correct if I leave the refresh rate empty, but I can't enter 1144 vertical total. if I try, it's in red.
The absolute lowest vertical total that isn't in red is 1448.
Yet yours is 1144.

Here's what happens if I Try to enter it in CRU:
test.jpg
test.jpg (23.63 KiB) Viewed 7917 times

can you do me a favor?
can you download ToastyX CRU and have it edit your custom resolutions and tell me what values it is using ? I will need horizontal total, vertical total, front porch/sync width, and the values that the Nvidia CP is not showing: Back Porch pixels/lines and Blanking pixels/lines.

About the 2720T:
You're referring to Lightboost, which was the "original" blur reduction, but this was designed to be used with 2d glasses. it was called Lightboost because compared to the original 3d vision, you could use the slider to make the 3d image brighter or darker (darker=better image quality, brighter=more blur). I don't know how this works with 3d, but I think it's 60 fps per eye, at 120 fps? I really don't know.

Lightboost was known to be quite dim, but this dimness was more due to the contrast ratio and color temperature plummeting (well, becoming too cool) as you could not adjust the brightness or gamma or color settings in Lightboost mode. Lightboost 100% wasn't too bad, though, and the 27" lightboost screens could keep a much higher contrast ratio than the 24" screens (the Benq XL2720T and XL2720Z can keep close to a 1000:1 contrast ratio in lightboost mode (but you get purple tent if you go above 37 contrast) while the 24" versions can barely keep 450:1.

Benq blur reduction is much better than this and is far more adjustable. Plus with changing the strobe duty combined with a Vertical Total 1498-1502 custom timing (not the resolution, just Vertical total, but this requires dropping the Horizontal Total to 2080 from 2200), you can get a screen that is much brighter than Lightboost.

For one thing, if you use the Vertical Total tweaks (as I'm sure you've seen mentioned all around), you can actually make blur reduction _brighter_ than non blur reduction brightness 100, with some extreme settings (but you lose most of the benefits of blur reduction), by forcing the LED backlight persistence -higher- than what the monitor was designed to use. For example, 120hz refresh rate is designed to use enough current to drive a 2.5 ms persistence for backlight strobing; the reason for these limits is because the backlight voltage is actually -increased- when blur reduction is enabled, to compensate for the screen dimming from the strobing flicker. You can actually see this if you try to use a refresh rate that does not have strobing information (like 50hz)--enabling benq blur reduction will cause the backlight to get massively brighter, as no strobe data exists for 50hz, and if the "strobe duty" (this controls the persistence) is higher than 008, the monitor will reset itself from overcurrent protection (the brightness gets north of 400 cd/m2, when the screen is supposed to be 300 cd/m2 maximum).

Using 125hz refresh rate with benq blur reduction and a custom vertical total of 1498 (VT 1500 and VT 1501/1502 cause strobe errors and lag on the XL2720Z) will give you a very bright screen at Strobe Duty 010, and you shouldn't have any of the annoyances you have with Lightboost on the XL2720T at 120hz. It's very very rare for people to be able to notice CRT flicker at 125-150 hz.

shreebles
Posts: 6
Joined: 13 Jul 2015, 10:48

Re: Question to BenQ XL2720T users

Post by shreebles » 15 Jul 2015, 10:49

Falkentyne wrote:
can you do me a favor?
can you download ToastyX CRU and have it edit your custom resolutions and tell me what values it is using ? I will need horizontal total, vertical total, front porch/sync width, and the values that the Nvidia CP is not showing: Back Porch pixels/lines and Blanking pixels/lines.
Here you go. Note that CRU did not find my previously created resolutions so I just put this in on the fly.
cru.PNG
cru.PNG (15.1 KiB) Viewed 7915 times
Note that I have switched monitors in the meantime. I got the 2720T today and took down the 2420.
Thanks for the details about lightboost, I see now there is more to it than I thought. However I really think I might regret an upgrade to the Z model as, like I said, I notice the strobing even though I can't see it. It just feels different to my eyes. Also, I am quite happy with my purchase as it is, and don't want to spend any more money.

In fact, I don't think I've ever been this happy about any second-hand purchase!
It has no dead pixels, no blemishes on the screen, and I've not been able to find any major scratches on the case. If there are any, they are certainly very small.
The 2720T does everything, and really well. I've been able to go up to 129hz (130hz gives the 'no signal' error, just like on the old one) on both 1920x1080 and 1920x1440. Unfortunately, CS:GO doesn't detect this resolution, but I've had more success with 125hz.
Therefore, I run both the desktop 16:9 and ingame 4:3 resolutions at 125hz. The info screen actually shows both these resolutions as being 1920x1080 @ 125hz. A positive side-effect is that alt-tabbing is much faster than before, despite switching resolutions.

The display seems brighter in general, so I am actually using 0 brightness as I am typing this (but I also have a headache so I need it to be as dim as possible right now). Despite it being huge I have more space now, because I can push the screen farther back and get more vertical space ( for my keyboards :D )
Now, all I need is a way to set Windows scaling to 90%. Some stuff is just too big at 27" FullHD.

Falkentyne
Posts: 2795
Joined: 26 Mar 2014, 07:23

Re: Question to BenQ XL2720T users

Post by Falkentyne » 15 Jul 2015, 11:03

Glad you like your new screen.
To set scaling, go into the OSD, go to picture advanced, go to display mode (or picture mode) then use one of the emulated screen sizes.
You can also use smart scaling if you use a smaller screen size but scaling a smaller size to 100% will still have interpolated pixel data.

Yeah those CRU timings don't work. Just says "out of range."
I think the Nvidia drivers are doing some weird stuff. The horizontal total can be set to some strange values (if you change the porch and sync) but the Vertical total hard limit is 1502.

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