Short update from my side: running the X32 FP via Nvidia 4080 or 4090 does not produce VRR dropouts in combination with DSC. So the combination of card + monitor matters. As a reminder, the same 2070 Super that caused massive VRR dropouts in combination with DSC ran without issues on a Asus 32uqxR that uses the very same panel as the X32 FP.

I still mostly disable DSC, though, because else either the driver or monitor loses MultiPlane Output (MPO) capability, no idea which of these to blame. This then causes VRR not to work for one of my games (Total War: Warhammer 3), because everything is output via Windows DWM composer instead of independent flip mode.

I looked further into the Brightness 97-100 issue. It only happens when local dimming is disabled, but also happens connected to the Intel iGPU via HDMI then.

My second X32 unit arrives a few days ago. Here are some comparisons of the second unit (B) to my first unit (A).

The Good (unit B vs. A):

• Considerably better - but still somewhat mediocre - backlight bleed on B, which also leads to better native contrast in those edge areas.
• Considerably less vertical “scanlines” on B, to the point of hard to even reproduce. I also noticed that A mostly produces “scanlines” in its horizontal center (third) only, but not towards the edges. Since this is especially problematic in HDR mode and seems to vary in strength I suspect that heat plays a role, too.
• The display on B can be moved up (1 cm) and down (2 mm) further on its stand. The stand of A seems to block too soon at its upper boundary as there is still some visibly free space on the guiding rails.
• Both units are audibly dead silent in all modes (SDR and HDR)!

The Bad (one or both units):

• B suffers from uneven white-point distribution over its screen area. It’s more greenish to the left and more purplish to the right. It’s subtle, but especially unpleasant (and noticeable) with brighter backgrounds (like white websites).
• Both units struggle with waking up from prolonged sleep when Windows enters display power-saving mode (not PC standby, just display). They hang, don’t react to button presses and need some fiddling with keeping the power button pressed or unplugging the power cord to get back a picture.
• The Acer Display Widget does not allow to control Brightness in HDR mode using firmware .09, .10 or .15, while the OSD does allow that with .15 at least. Controlling brightness via third party DDC/CI application throws both units out of HDR mode into a much darker User mode with .15, but doesn’t do anything in HDR mode with .09 and .10.
• Maximum brightness in SDR mode struggles to overpower my daylight room when I open the shades between morning and middle of the day. It gets better in the afternoon. Knowing that the monitor is capable of higher brightness and only artificially limited to lower SDR maximum is an unnecessary let-down.
• Dynamic Overdrive or having an OD setting between “Off” and “Normal” would be a welcome addition for using VRR at varying refresh-rates. “Normal” is often too strong below 160 Hz and Normal too weak above 120 Hz.
• Local Dimming cannot be set to one of the quick access buttons.

The Ugly (both units!):

• VRR + DSC connected via Displayport 1.4a to my 2070 Super still produces massive (!) dropouts on both units, especially in the 115-125 Hz range. I tried firmwares .09, .10 and .15, same results.
• Using Brightness 97-100 in HDR mode leads to considerable drop in brightness (and corresponding power usage at the wall) within 30 seconds on both units. Using Brightness 96 or less fixes this (and 96 is brighter than 97-100 then). No such problem in SDR mode.
• The tiny case frame around the side and upper display edges are slightly bend outwards, leaving gaps between frame and panel. This leads to backlight escaping through these gaps between panel and frame at the upper edges left and right and 8 discrete points along the upper edge of the panel/frame (single square holes towards the sides, double holes for the two center ones).

Bonus observations (both units):

• Local Dimming only ever completely disables LEDs for full black in SDR mode using Brightness up to 20 (fullscreen black, may vary slightly with mixed content). It changes in discrete steps every 19-20 Brightness levels. In HDR mode the backlight is never turned off for full black in any zone at any Brightness setting. Minimum HDR black seems to corresponds more to SDR step 3 (40-58) than step 2 (21-39). I speculate that this is to keep blooming and black crush in check.
• Firmware .09 already allowed to change Overdrive modes in combination with VRR, but only via Acer Display Widget, not via OSD. Firmware .10 removed that from both OSD and Acer Display Widget and only .15 re-introduced it to both.
• Firmware .15 also changed the brightness range when “Maximum Brightness” (MB) is disabled. Before it started at lower brightness (similar to MB enabled) but peaked lower at 100. Now Brightness 61 is the same as 100 was before and anything above uses local dimming black step 2 (same as 21-39 with MB enabled), but in return Brightness 0 is considerably brighter with MB disabled vs. enabled (and vs. older firmware).

Concerning the brightness drop in HDR mode at brightness settings 97-100, I measured power at the wall: 100% brightness showing fullscreen white drops from 172 W to 93 W in less than 30 seconds. 96% brightness stays at 167 W without dropping.

When the monitor changes from HDR to User mode by sending brightness commands via DDC/CI then it drops to 75 W and gets considerably darker.

At the same time 75 W in real SDR mode manages to reach close to the brightness of 167 W in HDR mode (hard to discern by eyes, needs measuring) and consequently is a lot brighter than 75 W in HDR mode.

Other users have not been able to reproduce this and I will get a second Acer X32 FP unit in a few days to compare.

Sep 13, 2023 04:09 PM By  Nicholas Di Giovanni

That is very interesting, thanks for sharing with everyone!

DDC/CI can also be disabled via OSD, so that could rule out any problems of that kind.

Sep 12, 2023 03:35 PM By Weissrolf

9

What I noticed is that when the monitor gets Brightness changes sent via DDC/CI then it switches to User mode and drops considerably in brightness. Unfortunately I own no PS5 to test this myself, but maybe the PS5 sends brightness commands to the monitor via DDC/CI and thus makes it switch to User mode and drop down to SDR brightness despite still claiming to be in HDR range. Anyone experiencing this should check if the monitor changes into “User” mode instead of “HDR”. If so then try to turn it off and on again and watch if stays in HDR then or switched back to User after some time. Alternatively try switching Picture -> HDR between “Off” and “Auto” to make it jump back into HDR mode. On Windows you can also fix this via Acer’s own software tool by switching back to HDR mode via that software. Unfortunately this does not work via OSD for “Modes”, so that one is a Windows only solution. On the other hand you cannot change Brightness via Acer’s Windows tool in HDR mode while the OSD allows to do just that. So changing brightness via DDC/CI seems to mess up that whole part of the system. Last but not least: my X32 decreases in brightness when HDR mode is used with Brightness between 97-100. This happens gradually after some seconds and his hard to notice. That is until you decrease Brightness to 96 and see brightness increase with the step from 97 down to 96. This brightness decrease does not seem to happen with Brightness setting up to 96, so I recommend everyone to not use above 96 in HDR mode.

That is very interesting, thanks for sharing with everyone!

Aug 30, 2023 09:02 AM By  Nicholas Di Giovanni

Honestly, we can’t say what caused this issue. It’s possible it was like this even when we were testing, but didn’t notice how dim it was, as we don’t measure the HDR brightness with the PS5. Sorry I can’t answer that question further!

What I noticed is that when the monitor gets Brightness changes sent via DDC/CI then it switches from HDR to User mode and drops considerably in brightness. Unfortunately I own no PS5 to test this myself, but maybe the PS5 sends brightness commands to the monitor via DDC/CI and thus makes it switch to User mode and drop down to SDR brightness despite still claiming to be in HDR range.

Anyone experiencing this should check if the monitor changes into “User” mode instead of “HDR”. If so then try to turn it off and on again and watch if stays in HDR then or switched back to User after some time. Alternatively try switching Picture -> HDR between “Off” and “Auto” to make it jump back into HDR mode.

On Windows you can also fix this via Acer’s own software tool by switching back to HDR mode via that software. Unfortunately this does not work via OSD for “Modes”, so that one is a Windows only solution. On the other hand you cannot change Brightness via Acer’s Windows tool in HDR mode while the OSD allows to do just that. So changing brightness via DDC/CI seems to mess up that whole part of the system.

Last but not least: my X32 decreases in brightness when HDR mode is used with Brightness between 97-100. This happens gradually after some seconds and his hard to notice. That is until you decrease Brightness to 96 and see brightness increase with the step from 97 down to 96. This brightness decrease does not seem to happen with Brightness setting up to 96, so I recommend everyone to not use above 96 in HDR mode.