Trying to connect laptop dvi outut to HDMI Input

[vettesea]

Hello

I have HP laptop with docking station (providing DVD-D Output) and a Sony Bravia 40 in full HD TV.

I am trying to connect the two using the DVI output, a Male DVI to Female HDMI adapter, and a standard HDMI lead to the TV.

I cannot seem to get any signal through to the TV whatsoever when I connect it all togother. I obviously chnage the output using Fn F4 and although the laptop tries to change output, there is no movement whatsoever on the TV.

Is there anything I am doing wrong, is this even possible? I have heard it could be a resolution issue, what can i do to resolve.

Thanks

[vettesea]

Come on, someone must know something about this, it is completely stumping me!

[jman98]

Check your TV's manual to see if it even allows this. My Samsung HDTV only allows PC connections via VGA and clearly states in the manual that DVI and HDMI won't work at all for connecting a PC to the TV.

[vettesea]

Hello

I have checked my manual and it reads as follows:

Connect to the HDMI IN 4 or 5 socket if the equipment has a HDMI socket. The digital and audio signals are input from the equipment. If the equipment has a DVI Socket, connect the DVI socket to the HDMI IN 4 socket through a DVI-HDMI adaptor interface, and connect the equipment’s audio out sockets to the audio in HDMI IN 4 sockets.
Notes.
• The HDMI sockets only support the following video inputs: 480i, 480p, 576i, 576p, 720p, 10801 and 1080p. To connect a PC, please use the PC socket

To me this reads rather conflicting. In one way it is saying if i can get my PC to output one of the above resolutions it should work. Then it says, us the VGA port for a PC.

Can I get my Laptop to output in one of the resolutions highlighted, or would you read this as it will not work.

Incidentally, I currently connect the PC using a VGA to component adapter and the TV inputs that OK at a 576i resolution, so that tells me it might just work if get it right.

[guns1inger]

It's not contradictory. What it is saying is if you want to watch video over DVI at one of the allowable formats, you can use a DVI-HDMI converter. However if you want to use it as a PC monitor, you the VGA connection. using it as a PC monitor will probably get you 1440 x 1080 or 1920 x 1080, if the VGA card can handle it. Much higher than using a VGA-Component adapter.

[vettesea]

OK, thanks for your response.

So, you agree that it "should" work if the outout from the PC is correct. I am currently getting nothing on the TV, not even a flicker. How can I try and get the output to match a valid input?

Thanks

[vettesea]

Another update with more detail:


I have a Sony KDL-40W2000 tv and am trying to connect a laptop (HP 620) via a docking station and DVI-D connection. I am using a DVI to HDMI adaptor and connecting the HDMI lead to the HDMI IN 4 socket.

Finally last night I got a 720p signal through using a resolution of 1280x720 output (on the second monitor setting with the graphics card (ATI Mobile Radeon 7500) I could not get the single monitor to the correct resolution). I cannot seem to get a 1080p or 1080i signal through, the screen remains blank.

The 720p signal suffers from overscan and my understanding is that you can set a full pixel setting on 1080i and 1080p only to prevent overscan.

Therefore I think my focus should be on trying to get the 1080i or 1080p working. Is 1080i simply 1920x1080 @30hz rather than 60hz?

Is there any reason why I can't get the signal through?

If I am stuck with the 720p signal, can i improve the overscan issue?

Thanks

[vettesea]

Hello

Thought I would update this. I found an option in the ATI control panel:

Reduce DVI frequency on high-resolution displays

As soon as this was de-selected the TV was able to display a full 1080p image. I could then set the TV to Full Pixel option to remove overscan and the image is great.

i had a few issues with lines flickering but i think that was a loose docking station connection, it was early this morning so i have additional testing to carry out tonight....

Would like to know exactly what that option has done and i am searching the web to find out.

[edDV]

Hello

Thought I would update this. I found an option in the ATI control panel:

Reduce DVI frequency on high-resolution displays

As soon as this was de-selected the TV was able to display a full 1080p image. I could then set the TV to Full Pixel option to remove overscan and the image is great.

i had a few issues with lines flickering but i think that was a loose docking station connection, it was early this morning so i have additional testing to carry out tonight....

Would like to know exactly what that option has done and i am searching the web to find out.

This has been covered many times. The VGA port behaves as a computer monitor port with square pixels and usually minimal overscan. 1366x768 (WXGA) isusually supported. Sometimes 1440×900 or 1680×1050 (WSXGA+) or other wide VESA resolutions are accepted. These are usually listed in the manual or you can call the TV set manufacturer.

The DVI/HDMI port wants video resolutions and it will overscan 5-10%. In order to display a computer desktop, the display card must shrink (scale) the image to compensate. Your laptop probably only supports progressive scan (no 576i/1080i) except via an analog component adapter.

The native resolution of your TV is 1920x1080 but a 1920x1080i/p input will show overscan by design. There is no such thing as direct pixel mapping with a TV. Everything gets scaled.

If you are seeing flicker, the TV may only accept 1080i. Pal sets want to see 50hz refresh rates. Some sets may accept 60Hz.

[vettesea]

Hello

Thanks for the response.

The TV is def Full HD compatible and can take 1080p (thisis endorsed by the fact that when the signal now comes though to the telly, it indicates it is a 1080p signal on the screen.

Regarding the full pixel bit, I do have an option to select Full Pixel in the Display Area of the menu (only when 1080i or 1080p is the throughput), the manual explains that this will then map directly from the dignal pixel topixel, it appears to be the case because the windows screen fits perfectly, no missing parts at the edge of the screen.

so, it seems good at the moment, I thought I had the thin lines sorted when I reconnected everything cleanly but then late last night halfway through a dvd the lines started to flicker again which was disapointing. It may well be a Hertz issue. Currently it is at 60hz, I could try 50 to see if there is an improvement. I also wondered if maybe it was the cabling or adaptor.
funny how it is intermittent....

[edDV]

Hello

Thanks for the response.

The TV is def Full HD compatible and can take 1080p (thisis endorsed by the fact that when the signal now comes though to the telly, it indicates it is a 1080p signal on the screen.

Regarding the full pixel bit, I do have an option to select Full Pixel in the Display Area of the menu (only when 1080i or 1080p is the throughput), the manual explains that this will then map directly from the dignal pixel topixel, it appears to be the case because the windows screen fits perfectly, no missing parts at the edge of the screen.

so, it seems good at the moment, I thought I had the thin lines sorted when I reconnected everything cleanly but then late last night halfway through a dvd the lines started to flicker again which was disapointing. It may well be a Hertz issue. Currently it is at 60hz, I could try 50 to see if there is an improvement. I also wondered if maybe it was the cabling or adaptor.
funny how it is intermittent....

Mostly great news there. That TV is rare. Does the flicker occur from still desktop images or just when playing a DVD? Is the flicker associated with moving objects?

See if you can get a good display with this test signal. Download and display the 1920x1080 TIF and display.

Do the arrows line up to picture edges on the TV?
Do you see flicker?
Are levels above 235 "whiter than white"?
Do levels 16 and below all look black, but level 20 showing brighter than level 16?

http://www.belle-nuit.com/testchart.html


If you only see flicker on moving objects, the problem is most likely refresh rate or MPeg2 artifact issues.

[vettesea]

Thanks

i wil have a further test this evening. It seems to me that when I start it up and for a little while it is fine. Then I start the DVD or AVI file and the thin flickery lines start up after a few minutes of that.

I will post back further results later.

[Kaushikdam]

Hi ,

I have a laptop IBM thinkpad T40 and a SONY Bravia HDTV. I am able to connect the laptop to my sony tv trough the 'PC IN' port and seeing only the visual part, but not able to get the audio output from tv.
I understand that I need a chord which would connect laptop to TV. But I am not sure what kind of cord I should use.
Can anybody please help me out ?

[vettesea]

Hello

I wish my problem was a simple as yours!!!

What you requie is a cable with headphone jack one side and red / white phono plugs the other, like his at Maplins:

http://www.maplin.co.uk/Module.aspx?ModuleNo=31700

Just plug it into the headphone out of your laptop and then into your tv input or stero/amp as I do.

[Kaushikdam]

Hi,
Thanks a lot for your suggestion.

[vettesea]

OK,

So this may well be the final post of this thread.

I changed the output to 50hz and since then the telly has been perfect. With 60 it sometime flicked and jumped when changing appliations and the thin lines would often appear. it was clearly having some trouble dealing with the signal.

The 50 Hz option appears to have resolved this and I have used it over the weekend with no ill effects so far.

So, in summary, my solution is:

HP laptop in docking station, hardware is a Mobility Radeon 7500 with latest drivers.
DVI to HDMI Adaptor
HDMI to HDMI Lead
HDMI Input socket on Sony Bravia KDL-40W2000 TV
Display settings on laptop are 1920x1080 with option for "Reduce DVI frequency on high-resolution displays" unchecked within the ATI Control Panel
Display frequency set to 50Hz on Laptop
Option on TV within settings for channel to set Display Area as Full Pixel (this removes any overscan issue)

And that as they say, is that....

Thanks to everyone.

[ColdPlays]

Hi!
I have 1 question though: How to set "Reduce DVI frequency on high-resolution displays" to be unchecked by default. Cuz with my CCC (v.2008.0225.2153.39091(?)) I cant shutdown at 1080p because CCC will ckeck the option again and I get no picture on screen.
I only have the option to shutdown in 720p mode and when started up again, switch to 1080p so I have to switch back afterwards to 720p in order to shutdown my pc..
Hence the question.

Thx
ColdPlays