Windows 7: Cannot switch back main display after connecting HDMI

Hi all,

I connected my HP Pavilion dv4-2165dx to my TV via the HDMI slot, and worked perfectly. I disconnected the cable from the notebook when I was done and still got the main LCD display to work. When I restarted the system, the LCD display was gone, just a blank screen with a backlight. The system is booting correctly, I can hear the windows7 startup sounds and even type my password in and access my account. So far I know that:

1. The screen hardware is not damaged, because after some reboots and taking the battery off for an hour I could get the input back with no problem (with windows complaining about being unable to boot and suggesting me to run Startup repair), but got a black screen again after rebooting again.

2. I can connect the HDMI again and get the output on the TV screen, but no main display is detected. If I toggle between displays with fn+f4, only the external HDMI-TV display works.

3. I get no startup screen either. That is, not even the first screen from where I can access the BIOS. But if I connect the HDMI-TV from the beginning I get all that info on the TV.

4. I reinstalled the Graphics driver from HP with no change.

My guess is that somewhat I messed up the default configuration and that the system is only recognizing the external displays as default displays. I haven't been able to modify this from the Control Panel - Display Settings menu, and I don't know where in the registry this default startup options could be.

Any help?

thanks!

did you uninstall the old drivers before installing the new one's ?
also you may try going to Control Panel\device manager\ display adapter and deleting the drivers from there then
reboot and install the new one's..

scrooge

Hello Iamec. If you had a blank screen how did you know you were in your account? If Windows was asking for Startup Repair, it likely didn't boot.
Did you set the TV as Extended, Clone, or Main?

Connect the TV to the HDMI and reboot.
Go to Control Panel, Display, on the left Change display settings. Click Detect and see if both display are shown. Click Identify and see what big white numbers show on the TV. It should be a 2.

Hi!

@scrooge: I did uninstall the old drivers first.

@Britton30: I can access my account with the TV display connected, and when it is not, I can hear the "login" sound after typing my account.

I got my screen back after some reboots and that's where I could see the Startup Repair. Indeed it didn't boot and got stuck. I rebooted and got the black screen again. I got that very same screen again and I chose to start windows normally and it booted as if nothing had happened. No other display was selected except the MobilePC main display. I restarted and got the black screen again.

The display is correctly identified as 2, but no other display is detected. And if I chose Display 1, I lose the TV display as expected but nothing comes on my screen.

Thanks for merging the posts! I couldn't find how to delete the other.

i think after you changed from display 2 to display 1 you need to unplug the hdmi so you can see your display on #1.
try it and see if that helps..

scrooge

I had a similar problem with my desktop PC and TV via HDMI. My monitor went black when I connected the TV, I wrongly assumed the display would be on both. But I had to go to the display adjustments as I told you to do, and set the TV as Clone in my case. I was trying to watch video from the PC to the TV, but quality was crap.
With the TV as primary, the monitor goes out. With the monitor as primary, theTV does.

After thought...is your laptop capable of using 2 display at once? Some can only use their connector for an external monitor, don't know if this is your case.