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The day before yesterday I bought 2M Sm@rtCom HDMI cable and succeeded duplicating laptop's screen to LG HDTV. Yesterday I tried again but this time the option for duplicating screen did not show up and I could only extend the screen:

enter image description here

I tried playing with resolutions, connecting to HDTV and then starting laptop, switching between HDMI cable's ends - all to no avail. The option disappeared. There was another option but it made 1|2 multiple screens in my laptop's screen to appear and nothing on HDTV.

UPDATE: It seems that do not have option to duplicate at all. Today I connected again but to different HDMI slot and screen appeared successfully on both laptop and HDTV:

enter image description here

However when I clicked on "Identify", both HDTV and laptop showed number 1. Shouldn't it be number 1 and 2?

I cannot change resolution by the way since the laptop's 1366x768 screen is cloned so it is a little wider than HDTV can handle, but still viewable. HDTV can handle a maximum 1360x768 but not 6 additional pixels. It can handle Full HD however.

It seems that Intel HD Graphics outputs HDMI while nVidia outputs VGA.

  • DELL Latitude E6420
  • Intel HD Graphics with nVidia NVS 4200M
  • Windows 7 Enterprise
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Have you updated your graphics drivers? – Sam Oct 23 '11 at 11:09
I have updated drivers. – Boris_yo Oct 23 '11 at 20:40

It seems that Intel HD Graphics outputs HDMI while nVidia outputs VGA.

That's indeed the only way to explain both screens are "1".

There will be some software built-in somewhere to manage this switching. Try:

The last two packages do some hardware control stuff, maybe they include the code we're looking for.

Did you try to disable nVidia Graphics (or Intel's), are you able to mirror the screen then?

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You mean that when duplicating/mirroring laptop's screen i will see 1 on laptop and HDTV? – Boris_yo Nov 5 '11 at 19:15
Sorry, don't understand your question. You mean you see the same on laptop and HDTV (which is just an external screen)? Then you're right. Isn't that what you actually were trying to do? – Jens Erat Nov 5 '11 at 20:56
Yes, 1 on laptop's screen and same 1 on HDTV. It is sad that i cannot control it and get this sometimes. I also am not able to control resolution since i guess when you are duplicating, you are duplicating. – Boris_yo Nov 6 '11 at 4:44
Even when duplicating Windows should detect the output and scale it to the display - as long as you have the driver installed for the remote display and the resolution set within Windows. – HaydnWVN Nov 7 '11 at 12:18
Remote display which in my case HDTV? If yes, then i have recent HDTV firmware. Thanks for informational steps. – Boris_yo Nov 7 '11 at 17:21

Where have you found the video drivers ?

You should try in the Nvidia download drivers page, the "GRAPHICS DRIVER" button under "Option 2: Automatically find drivers for my NVIDIA products".

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Original nVidia drivers are not good. Only to use DELL's. – Boris_yo Nov 3 '11 at 12:30
nVidia supplies the drivers for its cards to Microsoft and to Dell. So nVidia drivers are normally in advance of Windows and Dell. The drivers arrive in Windows Update after a long wait (sometimes counted in years) or they never arrive. You should use the driver that works best for you, so it is worth trying. – harrymc Nov 3 '11 at 12:49

Pressing the 'Fn' key followed by the 'F5' key should cycle between 'duplication' and setting the display as primary or secondary aswell as switching it off. In my experience these changes should be made before windows starts, if you wish to use it as an extended display (so windows can detect an additional display rather than just a duplicated one).

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This combination activates and deactivates touchpad and trackpoint. – Boris_yo Nov 5 '11 at 19:25
Read through your documentation, one of the Fkeys in conjunction with the Fn key will activate/change the display. – HaydnWVN Nov 7 '11 at 12:16
Thank you. You were right, but when i try to duplicate screen, i get 1|2 multiple screens on laptop's screen. – Boris_yo Nov 7 '11 at 17:19
You get both on the laptop? What on the external? – HaydnWVN Nov 8 '11 at 9:35
I get both on the laptop and black screen with my LG HDTV logo i.e nothing. – Boris_yo Nov 8 '11 at 14:12

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