My 27" FT45 monitor (LF27T450FQNXGO) goes into sleep mode and wakes up when it's supposed to. But while in sleep mode it will repeatedly turn on for a few seconds and back off. Continuously and regularly maybe every 10 seconds. What's on the screen is just what it was when it went to sleep; nothing changes there.
What's turning it back on? I've been turning the power off to make it stop at night or it will do this all night.
Oh, that's an interesting idea. My MB has integrated graphics and it's really old. This could also explain why Control Panel Devices calls it "Generic PnP Monitor". Everything else identifies it correctly. I looked for a new monitor on the Samsung site but that just isn't working; Search goes back to the Support home page (in Chrome, Firefox, and Edge). I'm going to see if there's a MB firmware update available. Haven't touched it in years.
I updated the onboard Intel 4600 Graphics using the Intel utility. That didn't change anything so I removed the monitor and rebooted to install it again. Control Panel now identifies it as LF27T450F but Properties shows the Manufacturer and Model number as "Unavailable". The driver is still "Generic PnP Monitor" and the version is dated 6/21/2006. It's still not identifying the monitor properly. I can't set it to use the Samsung ICC profile because it doesn't know it's Samsung, unless there's a Samsung utility that will help.
When I run the graphics update utility again it says everything is up to date. The Intel graphics driver it installed was released February 5, 2021 so not real recent.
The Intel HD Graphics Control Panel identifies the monitor as "Digital Television LF27T450F".
The behavior hasn't changed. The monitor still cycles on regularly though with just a dim screen, I think because it's on for too short a time to display anything before going off again.
And the computer is still coming out of Sleep mode after a short while but that's new and presumably unrelated. I might flash the MB UEFI to see if that helps though it wasn't happening before this (and happens with the Samsung monitor disconnected as well).
Thanks for your help. I think you're getting me closer to the problem.
i have the exact same problem, the computer is sleeping and the monitor goes off and every now and then, on, and then off again. also, anything that is showing in the monitor gets moved to the main screen if the monitor goes off. this didn't happen with the previous screens (also samsung), the computer didn't change, so i'm blaming the monitors
Thank you, Constellation, for merging these! And I'm able to reply now, too.
Sitting with the exact same problem , I have the C27JG50QQU and my pc is off, and connected to two monitors and only the Samsung switches on every 10 seconds. it’s annoying because I have an open floor plan upstairs where my pc is and the light from the screen can be seen while lying in bed.
OK, so I'm not the only one!
I haven't had a chance to try all the things that have been suggested but I decided to look into the system settings a bit more and then do a little testing and what I've found so far is interesting.
The sleep mode on the computer was indeed on despite what I've said, but I should have realized that because that's when the monitor does this. So I set the computer to not sleep. I looked at the additional setting and the power profiles and saw there is a profile called "Samsung High Performance". I don't know if that was installed by the monitor setup or the Samsung SSDs (along with Samsung Magician). Looking into it I saw it specifies that the computer never sleep but the display sleeps after 15 minutes.
So I set it to do that with the display going off after one minute so I could see what happens. I think this is done on the computer side, turning off the display signal to all monitors. The displays go off but the Samsung shows "HDM1" in the upper left corner as though it just got a signal, all in the same cycle I've noted.
It looks like there could be a signal coming from the computer, though I'm not sure this proves that. Why it's only showing up on the Samsung is a mystery. If the computer is sending something to one monitor it should be going to both.
When the displays shut off it's instantaneous. The Dell says it's scanning for a signal (Display Port), then that there's no signal and it's going into standby mode. The Samsung never does.
Maybe some of the others here who have commented on checking power and sleep settings will know more about what they are actually doing. Having the computer sleep is the usual for a desktop, I think, but for now you can do the same to at least keep the Samsung monitor from coming on. The computer can be set to sleep as well. Why the Samsung is doing this remains a mystery to me but this is a partial workaround.
More as I get a chance to check other things.
The Intel onboard graphics was updated. The Intel utility says there is no update available for the chipset. Behavior remains the same (with the odd added issue of the system rebooting while in Sleep mode for no apparent reason). I've set power to turn off the display instead of going into Sleep to avoid that, which would cause it to reboot regularly. The Samsung monitor (and not the other one) still cycles on and off, but just in a standby mode or about to go into standby, with the "HDMI 1" displayed (i.e., not displaying the desktop).
But this is hard to test now that I have this other problem, which is that the system will restart after it goes into sleep mode. Not a reboot as everything is back on the screen. More like hibernation, with system fans off and the Windows startup screen on the display. So I need to figure that one out before I can do anything more.