Dell E5440 laptop display will not turn off when docked

I have a Dell E5440 laptop that recently had it's LCD panel replaced. I usually dock it and connect it to an Optoma Projector and before I had the LCD panel replaced, I only showed 2 displays when I went to screen resolution. Now, after the LCD panel has been replaced, I see 3 displays in Screen Resolution, one of them being the laptop display.

Has anyone seen this behavior before and if so, do you know how to correct it? And before you go telling me to check my power setting in the Control Panel, my power settings are the same as they were before I had my LCD panel replaced. Also, I have upgraded the BIOS and completely wiped the hard drive and re-installed Windows.

At this point in time, I'm willing to entertain any and all suggestions.

Thanks,

Rusty

Why was the panel replaced?

Try to use the Identify command to find which screens are actually there.

Make sure the video firmware is autorunning on startup.

Perhaps the video driver needs to be reinstalled to adapt to the new screen, if the windows reinstall didn't cover that.

Hello Paul1149,

The panel was replaced because it had vertical lines running through it. I have used the Identify command and it definitely shows 3 displays whereas before it only showed 2.

The video firmware was updated after Windows 7 was re-installed. But I can always try and do it again. What's interesting is that I sent 7 Dell E5440 laptops in for the same problem. The other 6 are working just fine after the LCD panel was replaced.

This problem is driving me insane!

Thanks for your help!

I would go into Device Manager and look for monitors. Go up to View menu and check Hidden Devices. Maybe a tech plugged in a monitor while it was on the bench.

Thanks everyone for all the suggestions!

Could you post a screenshot of Screen Resolution please?

Can you select the 3rd monitor and disconnect it from the dropdown menu?
You can also try Win+P menu to switch between displays.