Connecting a laptop to a TV via HDMI

Question

I just bought a new Dell XPS17 laptop (Win7) that only has HDMI output. My last 2 laptops had VGA, which I used to connect to my Sony Bravia 32" TV with no issues, but with the HDMI it's been quite a headache.

Drivers for display adapters have been updated to the latest versions:

• Intel(R) HD Graphics Family
• NVIDIA GeForce GT 550M

I went to a store and plugged in to 4 different TVs from different manufacturers. A sales rep and I spent about 30 minutes being baffled by the results (which are the same as my current TV):

• Extreme buggy behavior in the Nvidia and Windows display/resolution control panel
• Can not extend or duplicate displays, can only select one
• Third and fourth output devices "randomly" detected by the Windows control panel
• Could not get the screen to fit the output (edges cut off on all sides by about a half inch)
• Resolution and colors less than perfect. Artifacts around text.
• Display "randomly" cuts out
• Defaults to TV output only when plugged in
• Can not change resolution on either device when connected
• No audio from the TV

Plugged in to 3 monitors from different manufacturers:

• Defaults to duplicated displays when plugged in
• Everything works perfectly

So far, four people have gone through all the settings in the latop with no luck. I had similar, but not exactly matching results with a different laptop.

I'm using the Sony Bravia currently at home, but in order to get it to work I have to turn on the laptop, wait until the display shows up on it, close the lid, then cycle through each output channel on the TV until I come back around to the HDMI port again, but still I have the symptoms described above.

However: Once in a while, it just works. Sometimes, seemingly randomly, the output fits the screen perfectly. Sometimes the audio comes through the speakers too, but not always. Usually my screen saver "Mystify" will come up with a message that it cannot be displayed due to a limitation of the video card, but then sometimes it works fine. These 3 things seem to be independent of each other and don't always happen together.

So, is there any way to get the laptop to output correctly to a TV, or is it just not meant to be?

Answer 1

The reason your output is cut off on the sides by a half-inch is probably the TV's "overscan" feature. There are weird artifacts at the edges of TV broadcast signals (even through a HD satellite or cable box) so they just scale the picture up a bit to get rid of that.

You need to change your TV's input mode. Some TVs call it "1:1" mode, "full pixel" or "true pixel" or something instead of just the 16:9 or auto aspect ratio mode.

This does not explain any of the other weird stuff though. You may be having issues because of the Intel HD and Nvidia graphics (I'm assuming it's an auto-switching system to save battery power). Is it a proper Optimus implementation or something Dell came up with? Maybe the switching hardware is screwed up.

Answer 2

Note: this should be a comment, but just too long (and i hate leaving multiple comments!)

Sounds very much like a faulty display adaptor/cable or some kind of interference - are the artifacts moving around/changing colour or remain static? Changing the cable is quick & easy (so very much worth eliminating!)

In my experience with the lid closed the external display will become the primary, yet before then (ie while windows loads and detects hardware) depending on the 'function key' setup it will either copy/extend or be off/disabled. Obviously when cycling this windows detects the change, but it might not always, it's worth scanning for hardware changes in device manager after making a external display change/swap. Now depending on the hardware/drivers will depend if this change uses different drivers for the display or not, if it does you will see Windows detecting more displays than you currently have.

We had one user on here (a few weeks back) with very odd display problems which was narrowed down to moisture causing the external display detection to act strangely.

Answer 3

You have several issues at hand; let's group and tackle them as appropriate (some may be interrelated):

• Third and fourth output devices "randomly" detected by the Windows control panel
• Display "randomly" cuts out
• No audio from the TV

These are all most likely caused by a poor-quality or under-spec'd cable. I'd recommend buying a highly-rated HDMI cable such as the AmazonBasics high-speed HDMI cable. Also, if you're using any sort of adapters, switchboxes, or other devices between the laptop and TV, try connecting directly to the TV.

• Extreme buggy behavior in the Nvidia and Windows display/resolution control panel
• Can not extend or duplicate displays, can only select one
• Can not change resolution on either device when connected

Once the random display cutouts and random device connect/disconnect issues are resolved, these issues will probably also go away.

• Defaults to TV output only when plugged in

This may also be partly related to the poor-quality video connection; but by default, many laptops do assume that you want to switch to the external display when it's connected. You can hold the Windows key and press P to switch to the built-in display or set the clone or extend mode. The laptop should remember the setting afterward, assuming you don't plug in a different external display and change the setting.

• Could not get the screen to fit the output (edges cut off on all sides by about a half inch)
• Resolution and colors less than perfect. Artifacts around text.

As evilspoons pointed out, your TV is in Overscan mode. These particular issues will be resolved by switching to 1:1, true pixel, or "Native" mode.

However: Once in a while, it just works. Sometimes, seemingly randomly, the output fits the screen perfectly. Sometimes the audio comes through the speakers too, but not always. Usually my screen saver "Mystify" will come up with a message that it cannot be displayed due to a limitation of the video card, but then sometimes it works fine. These 3 things seem to be independent of each other and don't always happen together.

Is it possible you're plugging into a different HDMI port sometimes? It may be the case that one of your HDMI ports is already configured for 1:1 mode, and you just happen to plug into that port the times when everything just seems to work.