*Now with pictures of AMA low in action*!
Since there isn't any clear information on how to enter the service/factory menus, in one clear spot, here it is.
(Chief can you sticky this?)
To unlock the factory and service menus:
Factory menu (not the service menu!)
1) power off via power button.
2) XL2411Z only: hold button #3 and button #5 with the power off, for 5 seconds, then press power while still holding them down. Release them after the screen appears.
2a) if nothing happens at all when the power button is pressed (this is most common after a firmware update or an AC hard power off), press power to give the monitor current, then after you get a display, power the screen off again, and then start sequence 1 again.
2b) XL2420Z, XL2430T, XL2720Z and XL2730Z, XL2735: buttons 3 and 4 with power off for 5+ seconds, and then pressing the power button while continuing to hold the buttons down, will unlock the factory menu.
3) button 5 enters factory menu.
(SERVICE MENU e.g. Strobe settings):
To enter the service menu (XL2420Z, XL2430T, XL2720Z and XL2730Z) with the single strobe (for single strobing refresh rates lower than 100hz), strobe duty, strobe phase and other settings: Turn off the monitor, then press and hold menu button #2 from the bottom. While holding this button, press the power button to turn the monitor on. The lights will flash, and when the monitor has turned on press button #2 once to enter the service menu.
In the service menu use button #5 (up), #4 (down) and #3 (select) to navigate the menu
5) For the XL2411Z (also the older XL2411T), it's button #2 (down button) for 5 seconds with power off, instead of button #4, then press power on+button #2
6) ON ALL S-SWITCH VERSIONS:
You can enter STANDARD MODE from any other mode preset, by holding down the top (back/exit) button on the s-switch, for 8 seconds+, then releasing.
You can save a preset to a gamer preset by holding down the preset button for 8+ seconds.
(May or may not apply to XL2430T and XL2730Z).
Note: the XL2730Z does not have the single strobe setting.
The XL2730Z will NOT strobe in sync at ANY refresh rate lower than 120hz!
Zowie XL2735 uses the same or a modified revision of the XL2730 scaler, Realtek 2796BF, and vertical total tweaks to lower strobe crosstalk work again. VT 1825 works at 2560x1440, and can be increased to VT 1852 by lowering the horizontal total.
This monitor will double strobe lower than 100hz, as the single strobe override is missing from the service menu. This monitor needs a firmware update to force single strobe for refresh rates 60-85hz.
*XL270Z specific feature--undocumented -- AMA low setting --removes ALMOST ALL INVERSE GHOSTING, adds normal ghosting, which can be removed by lowering the contrast setting!
XL2411Z, XL2420Z: AMA low reduces the inverse ghosting (helps a lot) but does not turn it into normal ghosting.
XL2430T: lower ghosting already properly calibrated for blur reduction properly. Profile switch bug can still apply much lower ghosting to blur reduction disabled.
1) enable blur reduction FIRST.
2) set AMA to high afterwards. If it's already on high, move slider to off/premium and back to high or just press Cancel (back button).
Or you can just highlight high and instead of pressing button #3 (enter), press button #4 (back); does the same thing.
Ghosting quality is far improved. This works best with a contrast setting of 10, based on 100hz refresh rate. Higher or lower refresh rates may be best with slightly different contrast. Gamma settings also affect this.
*NOTE: any change to preset profiles (except V5 firmware blur reduction off profile switching), resolution, refresh rate, Brightness (OSD) setting, (service menu --> Strobe Phase, Strobe Duty or Single Strobe On/Off) will instantly revert the AMA back. Contrast and Gamma and Color RGB, sharpness and black equalizer settings are safe to use.
The factory menu in the XL2730Z has a lot more useful (and arcane) debug information than in previous monitors.
Vertical totals, Strobe information, "Accelerated scanout" and the scaler: the scaler resolution (the resolution used internally, not the physical resolution) is shown in the factory menu (V3+firmware only). The Vertical Total affects the scaler resolution. Even the smallest change in default VT will affect the scaler. E.g. using a 1125 vertical total at 120hz (the default VT is 1144) will cause the scaler to report 1400x1050@120hz instead of 1920x1080@120hz.
Basic information on creating VT tweaks is on the main website FAQ As well in the Benq section of this forum.
But I'll just summarize: you need ToastyX custom resolution utility from here:http://www.monitortests.com/
For DVI connections, you will need the AMD or Nvidia pixel clock patcher for VT tweaks if the DVI dual link clock exceeds 330.00 mhz.
You will *NOT* need a patcher for displayport connections.
For basic timings, you want to create "LCD standard" resolutions under detailed resolutions for 1920x1080, for the refresh rate that you use the VT tweak for. Create LCD standard first (not manual yet, and don't just edit the 60hz entry that's already there unless you're intending to use a VT tweak for 60hz), so the default timings are created. For example if at 100hz and 120hz refresh rate, if your porch and sync values are 88 and 44, and horizontal total is 2200, then you did it wrong, those are for 60hz only. Once you create a LCD standard detailed resolution, then edit it and choose "manual" and you can change the Vertical total timings (or the Horizontal total for certain instances, like 120hz over displayport, to maintain 8 bpc color) as you desire.
Some technical information on what the VT tweaks do for strobing;
If the VT is increased past the default VT, the scaler switches to 60hz backlight strobe pulse widths (0.167ms per point of strobe duty = 0.167ms persistence at strobe duty 001, 0.167ms x 30=5.01ms at strobe duty 030).
The strobe crosstalk is determined by the internal vertical screen size the scaler is working with for strobing. Using a VT of 1497-1502 forces the scaler to work with a "Lightboost type accelerated scanout" equivalent of a 1440 vertical screen size (thus the reported resolution of 1280x1440)=25% lower strobe crosstalk, just like 1080 ->1440->25% larger size, because the scaler is calculating strobes for a 1440p vertical size on a 1920x1080 physical panel, driving most of the crosstalk "off" the physical range of the screen, but possibly degrading image quality slightly (faint scanlines effect on the screen, just like in Lightboost mode). it seems that Lightboost uses VT tweaks internally, which is why the highest VT is 1502, and why strobe crosstalk at 120hz lightboost 10% is pixel for pixel identical to VT 1500/120hz/strobe phase 000+strobe duty 009 (1.5ms persistence).
You can actually use this scaler trick to trick the monitor into accepting a 2560x1440 native resolution (scaler supersampling/downsampled): 2560x1440, front porch 48 pixels, 3 lines, sync width 32 pixels, 5 lines, Horizontal total: 2656, Vertical total 1500. Pixel clock will be 398.40 at 100hz. Only works from 61hz-100hz in 1 hz increments. 120hz will cause extreme artifacting in Displayport mode, black screen in DVI, due to scaler limitations. the strobe crosstalk will look identical to 1920x1080 without a VT tweak active. This will work over DVI with the pixel clock patcher. Displayport will be run at 6 bit color due to DP limits (8 bit color tops out at 360.00 MHz, 6 bit color tops out at 480 MHz)
Note: turning off "instant mode" seems to prevent the scaler from using the vertical total to calculate strobe timings when using VT tweaks (thus VT gets ignored; any faint scanlines effect from VT 1500 will be gone), but at 120hz+, the screen will become scrambled.
The XL2730Z uses a realtek scaler and seems to ignore vertical totals increases for strobe crosstalk reduction, unfortunately, even though higher VT's are accepted and shown by the debug information (similar to instant mode off on the older Z series).
On an XL2720Z at 100hz VT 1350 doesn't sync correctly. whether or not blur reduction is on or off. There are occasional pauses and frameskips even with MBR off, although it's easier to see if its on. VT 1354 works correctly. Both VT 1500 and VT 1502 also work correctly.
On an XL2720Z at 120hz, VT 1502 doesn't always sync correctly. VT 1499 and VT 1500 are fine. Oddly enough at 125hz, VT 1502 syncs correctly (sometimes it may go out of sync and stutter if you spam the S-switch profiles, though), same with VT 1498 (VT 1500 was a bit problematic). Here are some solid VT totals on XL2720Z only (with no frameskipping or a <5% chance of frameskipping; if it happens just press the S-switch to retoggle the monitor); they may differ on the 24" versions!
These VT's work best :
*notice* for VT tweaks, excluding 60hz, you should use the base default values for 100/120hz, as shown:
1920x1080, front porch 48 pixels, 3 lines; sync with 32 pixels, 5 lines; Horizontal total 2080, vertical total 1354/1360 (60hz), 1360 (75hz), 1354 (100hz; low reduction of crosstalk), 1497-1502 (high reduction of crosstalk, most refresh rates, use whichever value does NOT cause frameskipping in this test: http://www.testufo.com/#test=photo&phot ... &height=-1
; frameskipping is very easy to notice with blur reduction)
For high reduction of crosstalk, these VT's are most reliable on XL2720Z. The 24" monitors may show different results.
120hz: HT 2001, VT 1499 (Displayport input; reduced HT to keep 8 bpc over displayport), VT 1500 (DVI input). I did not test VT 1350-VT 1354, but if you want lower/no faint horizontal lines artifacts but with more strobe crosstalk, HT 2080 and VT 1350-1354. Always test for frameskipping in TestUFO alien invasion !!
100hz: VT 1502, VT 1354 (VT 1354 has 18% more strobe crosstalk than VT 1502, but no faint horizontal lines scanlines artifacts. Chief's recommendation of VT 1350 *always *frameskips on XL2720Z so it's unusable, but its sporadic. Maybe XL2411Z and XL2420Z don't frameskip. I recommend VT 1500/1502).
91hz: VT 1498 (VT 1502 works but has a small chance of frameskipping. 91hz is for Call of duty framerate limits on some versions)
85hz: VT 1501 (all others frameskip heavily on XL2720Z)
80hz: VT 1498, VT 1501 (VT 1502 will frameskip at least once every 15 seconds)
75hz: VT 1360 (no frameskipping)
60hz: VT 1354, VT 1360 (displayport only; for DVI see masterotaku's recommended settings. The pixel clock at VT 1350'ish area interferes with the single link DVI limits which isn't a problem over DP)
For most other bizarre custom refresh rates, you will have to test. Usually VT 1502, VT 1498 and VT 1500 tend to work more often than the others.
Some XL2720Z *Display scaled* custom downscaled resolutions (scaler supersampling) that work: (XL2720Z, XL2420Z is mostly untested).
1) 2560x1440@100hz (displayport and DVI with pixel clock patcher, works on XL2720Z, 2420Z, 2411Z and maybe 2430T): use HT 2656-2720, VT 1498-VT 1502. (front porch 48 pixels, 3 lines; sync width 32 pixels 5 lines). Pixel clock 408.55 MHz @ HT 2720 and VT 1502. Monitor will run in 6 bits per color due to 360 MHz displayport 8 bpc limit (monitor does not support high bit rate 2)
Crosstalk will be identical to XL2730Z's default crosstalk at 2560x1440@100hz.
2) 2560x1440@115hz (Displayport ONLY): Use HT 2641 and VT 1497. Pixel clock 454.67 mhz. Any higher will give you shimmering pixels. You are pushing the scaler past its limits. YMMV.
3) 3200x1800@60hz (displayport ONLY): HT 3360, VT 2220, pixel clock 447.56 mhz. Yes this is the VT range for 4k (3840x2160). Monitor will show an out of range black screen error with default VT for 3200x1800 (VT tweaks at work again).
*MONITOR BACKLIGHT WILL SHUT OFF IF SINGLE STROBE IS TURNED OFF. With single strobe enabled, monitor will *DOUBLE STROBE*. Strobe adjustments will not do anything. Strobe scaler was not meant for these timings. OSD will report 1080p@24.
4) 3840x2160@30hz (displayport only, automatic timings): yes it works. Yes it's useless and laggy at 30hz. Input lag is off the charts (I used the VT from this to get 3200x1800 working).
5) 120hz with high VT Tweak over displayport, 1920x1080 8 bits per channel trick (usually the monitor switches to 6 BPC if you use a high VT tweak at 120hz over displayport; DVI with clock patcher applied does not have this limitation: (applies to XL2420Z and XL2430T also).
HT 2001, VT 1499 (front porch 48,3 ; sync width 32,5) keeps the pixel clock at 359.94 MHz for 8 bits per channel color.
6) High values of strobe phase give you ONE FRAME of lower (faster/reduced) input lag than strobe phase 000. Strobe phase 000 gives you lowest crosstalk at the bottom of the screen. Changing strobe phase to a higher value pushes the start of the strobe (backlight on/off cycle) EARLIER into the refresh rate. Max strobe phase without VT Tweak is 100 (1 frame improved input lag vs strobe phase 000).
Max strobe phase WITH VT Tweak depends on refresh rate--going any higher will shut off the backlight:
these are based on a Vertical total 1497-1502 range (1280x1440 scaler resolution shown in the factory menu).
91hz: 065 (single strobe=on)
85hz: 070 (single strobe=on)
75hz: higher than 85hz (Note this uses VT 1360; attempting to use VT 1500 will go out of range 90% of the time).
Using a vertical total higher than the default VT for the refresh rate makes the backlight switch to the 60hz strobe pulse widths.
TFTcentral has a nice article on what a "pulse width" actually ishttp://www.tftcentral.co.uk/articles/motion_blur.htm
XL2720Z Blur Reduction off AMA LOW TRICK* --absolutely NO OVERDRIVE GHOSTING.
(this has been tested on XL2720Z V5....I do not know if it works on V4. The blur reduction AMA low trick works on V3 and V4 though).
1) activate XL2720Z blur reduction AMA low mode by (a) first setting blur reduction to enabled, then going to AMA, moving AMA slider from high to off/premium then back to high (or just highlight high and press cancel (button #4).
2) use profile presets or S-switch to activate Standard mode (you must have blur reduction set to off previously in this mode you are switching to).
Unlike blur reduction AMA low mode, changing brightness does not reset the AMA if blur reduction is off. Changing refresh rate or resolution, however, will revert the AMA.
(note: blur reduction on AMA high (setting AMA to high when blur reduction is off and then enabling blur reduction) by default has a slightly lower overdrive setting than blur reduction off AMA high). You can get blur reduction off use the "slightly lower" AMA high setting by doing the same thing--switching to a preset profile that has blur reduction off. Doesn't look as good as AMA low blur reduction off, though!
No, people, you cant just set MBR AMA to low then turn OFF blur reduction...for some reason turning off blur reduction directly resets the AMA. But changing the profile preset seems to avoid this (Another beneficial bug, eh, Benq ? Just like our VT tweaks?)
This now makes the XL2720Z (with blur reduction off) look identical to Asus VG248QE with Tracefree=60.
And you can keep the contrast high also without needing to lower it
(AMA low with blur reduction enabled requires contrast 5-15 or there's a lot of normal, instead of inverse ghosting).
(remember in order for this to work with blur reduction off, you must first enable AMA low with blur reduction ON, then switch directly to a preset that has blur reduction off. Just turning off MBR does not work).
I might flash back to V4 later with the Mstar ISP unit to see if this works on V4 firmware.
*THERE IS ABSOLUTELY NO reason in the world NOT to use this AMA low mode if you do NOT use blur reduction! There is absolutely NO drawbacks to it, unlike blur reduction on AMA low, where the drawback is you have to lower the contrast to not have too much normal ghosting. Looks PERFECT with contrast 43.
Just in case the above steps led to any confusion, I have another explanation I wrote which should make it even more clear:
BLUR REDUCTION OFF PERFECT OVERDRIVE CALIBRATION for XL2720Z (firmware bug exploit); V3-V5 firmware. 24" panels benefit also but to a far lesser level: NO white ghosting trails, NO coronas, looks BETTER than VG248QE and VG278HE ! Makes ghosting on XL2720Z look better than any monitor on the market. This is for people NOT using blur reduction.
1) Set standard mode to blur reduction off, AMA high, contrast 43 (correct white delta). Save it to a gamer 1-3 preset (otherwise you need to use the 10 second S-switch standard mode quickselect).
2) set a gamer preset next to the first one, to blur reduction on, AMA high
3) activate MBR on preset with S-switch (XL2411Z users need to do it the long way).
4) Activate the "AMA low" XL2720Z toggle by setting AMA to high after MBR has been enabled (as mentioned above).
5) Activate the blur reduction off preset directly. If you did not save one, hold down "Enter" on the S-switch for 10 seconds then release it. This switches to standard mode (which I Hope you set with MBR off as I said in #1).
6) Standard mode (MBR off) will now avoid AMA recalibration from turning off MBR, and will use the AMA low setting instead of the default setting for MBR off. Ghosting will be _perfect_ (you will have sample and hold motion blur still, of course) but NO coronas, NO white trails following dark objects, and no normal ghosting or inverse ghosting. Compared side by side with VG248QE at tracefree 40/60, this looks better. 60hz-144hz all look great with this.
Note: changing resolution or refresh rate resets the AMA back to the aggressive AMA high level. Changing strobe phase/duty/single strobe or OSD brightness will not revert the AMA as blur reduction is off.
XL2411Z and XL2420Z (V3+ firmware) also benefit from this but to a far lesser level. There is NO reason NOT to use it as its much improved over default, but there is still some inverse ghosting. XL2430T has not been tested.
*Relationship between Strobe Duty, Strobe phase, refresh rate, and persistence values (aka strobe pulse width values; total strobe persistence = base strobe persistence x strobe duty value):
Pulse widths (base persistence at strobe duty 001) = Refresh rate persistence / Maximum strobe phase
Refresh rate persistence is always based on the current refresh rate, this applies to oddball refresh rates like 80hz, 91hz, 85hz, 75hz etc as well.
Refresh rate persistence= 1000 divided by current refresh rate in milliseconds, e.g. 60hz=16.7 ms, 100hz=10 ms, 120hz=8.3ms, 144hz=6.9ms.
VT tweaks force the Pulse Width base persistence to 0.167 ms (=the 60hz pulse widths), so since the refresh rate persistence remains the same (with or without a VT tweak at the same refresh rate), the MAXIMUM STROBE PHASE allowed is reduced. Going beyond the max strobe phase will shut off the backlight. Check the math--it's easy and adds up. Normally, the maximum strobe phase is 100, when not using VT tweaks (and sure enough everything adds right up, based on the strobe phase max values I listed way above). However, when NOT using a vertical total tweak, the maximum strobe duty does NOT decrease as the strobe phase reaches 100; there seems to be a buffer to prevent this from happening. You would expect that strobe phase 100=max strobe duty 001, strobe phase 099=max strobe duty 002, but there seems to be a buffer to allow higher strobe duty at the max strobe phase.
Using a VT tweak seems to REMOVE this buffer completely (which should also improve input lag by a TINY amount as well), so at the max strobe phase before the backlight shuts off, the strobe duty is always 001; at the max strobe phase -1 (minus 1), the max strobe duty is always 002, and so on...(Chief mentioned that using a VT tweak somehow improves input lag, now we know why; note though that strobe phase of 000 has 1 frame HIGHER input lag than max strobe phase, as lowering the strobe phase pushes the strobe into the *NEXT* rendered frame instead of the CURRENT rendered frame (100 strobe phase or max strobe phase with VT tweak)
Linked some XL2720Z only 60hz and 100hz Blur reduction OFF + "perfect overdrive" AMA low pictures, and some improved AMA low blur reduction on pictures:http://www.overclock.net/t/1580147/xl27 ... -off-trick
Some AMA "low" blur reduction on pictures (comparing the default AMA high and the undocumented toggle AMA low) here:http://www.overclock.net/t/1576752/best ... -gaming/20
Stuck 60hz at 2560x1440 on XL2730Z (displayport) fix: (assuming you are using a certified DP 1.2+ cable)
1) Power off
2) Hold Button 3 and 4, Power On ( while still holding Button 3 and 4 ), after 5 seconds release it.
3) Click any OSD Buttons, enter Menu and it will display the Factory Settings Menu, navigate it via the OSD Buttons, select CLEAR USER. Monitor will reset.
4) Power off monitor, unplug it from the power cord from 30+ seconds. Hook and power it back up. 2560x1440 should have all of the refresh rates again.
*Edited with pics of low AMA*.
Updated with comparison pictures of what AMA low mode does to improve the monitor (Based on XL2720Z V3-V5 firmware. XL2420Z, XL2430T, XL2411Z will have improvements, but much less (basically, minor improvements rather than major improvements). V2 will make the AMA twice as bad so V2 cannot be used.
Blur reduction on, AMA high, default (This was taken at 120hz, strobe duty 009, contrast 43 (1.5ms persistence with VT tweak) with strobe phase at 000.
Blur reduction on, AMA low, contrast 43 (don't remember the refresh rate but it is irrelevant--this is how it looks).
You can VISIBLY see the difference massively. All inverse ghosting has bee reduced to the point of normal ghosting. While this is a 'big' swing in the opposite way from a perfect calibration, sometimes on 2D side scrolling games it helps. Sometimes the minor XL2420Z/XL2411Z boost is better. You can improve this on the XL2720Z even more by dropping contrast from 43 to 10.
120hz, AMA low, contrast 10, Strobe duty 009, camera exposure time -2.0 to make moving images clearer (that's why the screen is so dark, NOT the contrast 10, although lowering contrast does make things more washed out and has an effect on brightness in a way, but not on the backlight directly).
The BENEFIT of the XL2720Z "overshooting" the AMA low so much is a HUGE benefit to blur reduction OFF, by using the bug in the first post with profile switching. This is because, blur reduction off's AMA high is basically the same as blur reduction on's AMA premium! So the 'AMA low" is shifted heavily towards the right if you do this, making blur reduction off's AMA not show hardly ANY ghosting whatsoever--ZERO inverse ghosting and barely zero normal ghosting!
The XL2420Z, XL2411Z, 30T etc would all show inverse ghosting, but obviously less, but not much less.
Here is 100hz:
100hz, blur reduction OFF, AMA high.
100hz, blur reduction OFF, AMA low, by switching to a preset (gamer 1/2/3) that has blur reduction off, after doing AMA low with blur reduction on.
Pics speak for themselves.
Firmwares are here: https://onedrive.live.com/?authkey=%21A ... CB73592A44
Use http://www.yoycart.com/Product/52781882 ... ment_tool/
to flash the firmwares with instructions/software from here: http://www.blurbusters.com/benq/diy-fir ... -z-series/
You can use Linux (my instructions on page 21) AT YOUR OWN RISK. If problems happen, the Mstar device can recover from bricking. PLEASE USE A LEGACY(old school) BIOS, NOT a UEFI BIOS to flash.viewtopic.php?f=13&t=779&start=200