I just received this monitor and I'm also having issues with the HDMI 2.1 Ports. The entire bottom third of the monitor flickers and stutters when I set it to 240hz, but does not do it at 120hz. The display port does not have this issue though. I have tried a RTX 4090 and a 4070 and both do the same thing on the HDMI 2.1 ports.

And you are right, it seems to be the Gsync, when I turn it off everything is fine, when it is on and I'm connected to the HDMI 2.1 then the flicker comes back. Seems a firmware update is needed ASAP, this is not okay for a monitor in this price point.

@Synthetic Pulse​ mine does the same thing just got it to day your right needs a update for 240 asap 

@Maples11​ Have you had any luck contacting dell? The automated service just said my order number did not exist and then hung up on me, I don't think this is okay for the amount we paid for this monitor.

You are using the included HDMI cable when testing this, correct?

And the video card output is HDMI 2.1?

Same issue here. Im using an RTX4090. THe hdmi 2.1 flickers and tears, but the DP works fine. My main issue is the HDR. It doesnt seem to be working properly. I wish there was a way to turn off Dolby Vision (DV). It seems that its stuck in DV on the desktop, but when I start games that do not support DV the hdr looks a little washed out. Also when i select different Smart HDR settings, they all look the same. I have been reading about this issue on the net. People are saying to roll back the RTX 4090 driver. We should not have to change that in order for this to work properly. Im guessing there will be a Firmware update? Im hoping sooner rather than later... 

I've been reading about various issues including this one.  I'll just chime in with I got my monitor on the Saturday after you could order.  I'm using a Galax RTX 4080 and the HDMI cable that came with the monitor.  Have the monitor set to 240 for refresh and have no flickering or tearing.  While I'd say in games that don't support HDR natively (like World of Warcraft) the auto HDR from Windows 11 might look a little washed out sometimes.  I haven't gotten around to messing with settings or haven't felt like it.  In games with HDR support I haven't had any issues... again I've read about them in various places.  Although I only play 3 games at the moment and the other two have HDR support built in.

Adding my voice to this remaining a problem.  2 issues:

• G-Sync causes horrible tearing and flashing at 240hz when using HDMI (3070ti - multiple cables tested)
• HDR enabled in Windows on latest Nvidia drivers (546.65 and 551.23 both confirmed) cause Dolby Vision to kick in.  Reboot and changing HDR mode on monitor when not in Windows HDR does not change this behaviour.  Further:
  • In games with this situation, HDR "works" but is washed out and doesn't show peak brightness
  • Rolling back to Nvidia driver 546.17 fixes the Dolby Vision issue, indicating it is not a hardware issue.  When this is done, HDR 1000 mode works and HDR looks great in games.

HDMI Issue here! Same 4090 card, HDMI 2.1 cables  to AW3225QF

Like many others, the problem is with using HDMI. No issues with DP 1.4. 

When I use HDMI, the screen constantly flickers and turns off & on. No amount of changing cables, HDR or Geforce settings helps. 

Please add details on monitor connections. Single monitor, or dual?

Also, this could be a driver issue and not a monitor issue.

The RTX 4000 series cannot drive 2 x 4K at 240 Hz, only can drive it at 120 Hz. There seems to be a limitation with the HDMI 2.1 implementation of the 4000 series.

See the table and comments at this article: RTX 4000 table

" What makes this a little strange is that even though the GeForce RTX 4090 doesn't support the new DisplayPort 2.1, the full HDMI 2.1 spec of the card should theoretically have enough bandwidth to support 240 Hz - as its possible with the Radeon RX 7900 XTX over HDMI 2.1."

We will have to wait until someone with a Radeon 7900 card tests the HDMI out, to see if it works properly or not to rule out the HDMI 240 Hz implementation of the 4000 series cards. The fact it works properly using DP has me leaning towards an issue that is not related to the monitor.