1) Disabling ESLogo

This option in the service menu means "Energy Star logo" and on some monitors, it does exactly that: disables the "Energy Star" icon on the "No Signal" screen during the 5-minute Power Save Mode timer. However, on others, it will disable the timer entirely. There is no much harm in trying that AFAIK, and you can always come back.

1. Boot the monitor into "Service Mode".

• Booting into "Service Mode" Service Mode is a pre-requisite to entering Service Menu. There are 4 unlabeled buttons on your monitor, from left to right (or top to bottom) - we'll call them ①②③④ - as well as the ⏻ Power button. Power off your monitor by pressing the ⏻ Power button. While holding down the first two buttons (①②), press the ⏻ Power button. Release all buttons. You should notice that the monitor displayed no information about the currently selected source and there is extra text in the header of the usual menu.

2. Open the Service Menu.

3. Navigate to "ESLogo" and turn it OFF.

• Navigating Service Menu This may be different between monitors. Tip: Take a picture of the menu before you navigate it! In this menu, you will not get hints which button is which. On my monitor: ①: Up ②: Down ③: Enter/Back ④: No Function

4. Navigate to "Exit" and confirm with ③ to exit Service Menu.
5. Use the ⏻ Power button to turn your monitor off and back on to leave Service mode.

If the issue persists, there is another option:

2) Using Energy Smart Mode

In Energy Smart Mode, Dell made the right decision that saves energy: disabled the 4- or 5-minute timer! However, there is a picture quality downside I will mention later. There is no harm trying, though.

Again, this might not apply to your model.

1. Open the regular menu using the buttons.
2. Go to Other Settings > Energy Smart.
3. Turn it On.
4. Press Back repeatedly to exit the menu.

You may now notice that the backlight intensity changes based on the overall brightness of the displayed content, with a bit of a delay. If you find this annoying, try turning brightness to 0. If this is too dim, try the following.

(Warning: This worked for some, but it disabled backlight on my monitor! I could go back by pressing "Up" or "Down" again. If you accidentally turn off the backlight and move away from the option in the menu, you can use a flashlight at a sharp angle to see a part of the screen, enough to navigate the Service menu and undo the changes.)

1. Boot into Service Mode and open Service Menu (see above).
2. Navigate to DCR (dynamic contrast ratio). This adjusts the backlight based on content.
3. Press Enter/Back (③) to enter the option.
4. Press Up/Down (①/②) to toggle On/Off. If your backlight turns off, press Up/Down (①/②) again to toggle the option back!
5. Press Enter/Back (③) to confirm.
6. Try opening windows/pages with different overall brightness and check that the backlight intensity is indeed constant.
7. Exit Service Menu and Service Mode (see above).

3) Always using Service Mode

This "fix" works because in Service Mode, the monitor does not show any OSD (other than the normal and service menu). You will also not see which source is currently active but most people use only one anyway.

The problem is, powering off your monitor using the ⏻ Power button or by unplugging power will exit Service Mode and you will need to re-enter it. To just do this once, you need to keep the monitor in Power Save Mode - however, it only uses 0.05 W so there is not much reason to not do this.

This "fix" only has one step:

1. Every time you power on the monitor from the off state, enter Service Mode by holding the first two buttons ①② (left- or topmost ones) while you press the ⏻ Power button.

Recommended to write down this step in case you turn the monitor off accidentally and want to remove the timer again.