It's one of those areas you learn to avoid. If you connect from VGA to VGA, HDMI to HDMI then you usually are good to go.
HDMI does have a rather bad issue with HDCP. Once in a while I find the old HDCP reset to help. It's pretty simple. Unplug the HDMI cables from the TV and then remove the mains power for about 5 or more minutes. The chips reset and then you retest.
Hello, I'm having a recurring problem connecting Dell Laptop to Samsung TVs as 2nd display... I've used several combinations as follows:
1. Samsung UE40J5200 TV connected with Dell Latitude E6400 over Display port + D-Port - HDMI conector + HDMI -HDMI cable - worked great for about 3 weeks after which suddenly stopped working; tried the same laptop with VGA - HDMI cable on a philips monitor and worked; VGA-HDMI on same Samsung TV didn't; reinstalled HD Graphics 4000 drivers - useless; reinstalled Windows7 SP1 - useless; tried same laptop with different Samsung 7Series, - useless; practically that laptop stopped working either over VGA or d-port with Samsung TVs HDMI inputs forever. Lots of forums read, but didn't find any solution to work. I mention that I have also an XBox connected over HDMI with the same TV - works 100% fine in any HDMI port of TV;
2. HP Elitebook over d-port + same dport - hdmi convertor + HDMI cable worked all the time with Samsung UE40J5200 TV;
3. Latitude E5430 - over HDMI port with HDMI cable connected to UE40J5200 TV (same Windows 7 SP1) worked fine once again for ~3 weeks then suddenly stopped working; VGA - HDMI - not working either. Tried once again drivers uninstall+reinstall, TV reset to factory settings, plugging and unplugging TV / connectors, changing HDMI ports for a day long - useless.
TV is not receiving any signal while Display properties on Dell laptop is not detecting second screen. Even forcing to send signal to a 2nd screen over VGA or composite didn't changed anything.
I'm using switching from single display to Duplicate or Extend with FN+F8 or windows key + P , I'm switching sources on Samsung TV from one HDMI port to another each time but without any success.
After 8 hours of work I call your help...

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