I'm the semi-proud owner of a new Panasonic 50PZ80 TV. Unfortunately, I've encountered a large problem in using it with my HTPC. Currently I have a Windows MCE box that I have hooked up to the HDMI 1 port with a DVI-to-HDMI cable. If I turn the screen on, then power up the computer, the image loads and everything displays fine and great. (I do love the picture, by the way.) If however, I turn on the PC before I turn on the TV, the TV will fail to recognize the video signal, and will flash an error code on the power light. (I'm not sure the exact code, but I believe it flashes 10 times.) The problem with this is that I cannot have the PC on beforehand or leave it running and then turn on the TV.

I contacted Panasonic technical support about this. Their somewhat knowledgeable (but rather rude) staff informed me that this has to do with the fact that the "TV was not made to be used as a monitor.", and that this was a, "known issue." I pried a little more and I was told the following that I will try to summarize to the best of my ability:

I was told that the HDMI 1 and 2 ports (on the back of the TV) are different than the HDMI 3 port (on the front of the TV). I believe they said that port 3 was unbuffered while the other two were buffered. (This could be vice versa.) They suggested that I try to hook the PC up to port 3 and the PC may work there. I did so, and they were right, I can turn the TV on and off with the HTPC plugged into port 3. They went on to say something about a "3.3V signal" that from what I could interpret was used to tell the TV to wake up or sync up.

Naturally though, with my sleek new TV that is very cleanly wall mounted with no visible wiring, leaving a PC attached through the front panel is not an acceptable solution. This leaves me with three options (none of which very cheap) that I have come up with in an attempt to remedy my situation:

1) The HTPC that I have is (admittedly) somewhat old. The graphics card in it is a GeForce 6800GT AGP. It has two DVI outputs on it. I was already planning on upgrading my HTPC sometime in the near future, and in doing so, I was going to either get a motherboard with onboard HDMI or a video card with native HDMI. Is it possible that this will fix my problem? My assumption is that in going with a video card or motherboard with native HDMI, it will be HDMI standards compliant. I am assuming that conformance to these standards will address the issue that I am having. Again, this is an assumption, I don't know if it will work.

2) Purchase an AV receiver that handles HDMI switching. It is my hope that the AV receiver will be able to handle the DVI-to-HDMI cable and output the necessary (buffered or unbuffered, whichever is correct) signal to the normal HDMI 1 and 2 ports.

3) Purchase an HDMI switcher that may perform the same task as the AV receiver. Although I would only have one device attached, I hope that the switcher will be able to provide the necessary "wake up" signal to the TV.

Also, one of their suggestions was to use this HDMI to HDMI adapter:

http://www.jascoproducts.com/products/pc/viewPrd.asp?idcategory=0&idproduct=440

Which I just can't fathom how that could possibly work. Its just a 1:1 adapter from all I can tell and I can't see how that's any different than just using a DVI-to-HDMI cable.

I'm sorry for the long winded post, but I'm completely stumped. I searched the forums' tome of knowledge and couldn't find anything that fit my particular problem. Thanks in advance to all who can provide input.

Dustin Earnhardt

I have a Panasonic 50 inch as well (PX77U).  I am not sure if mine has the "buffered/unbuffered" HDMI ports, but I have no problems with my system in HDMI 1 or HDMI 2 on the back of the TV.

My setup is a Dell XPS 420 with an ATI 2600 XT.  It has dual DVI.  I am using the included DVI-HDMI adapter connected to an HDMI cable.  I leave VMC on all the time and turn the TV on/off as needed.

So, this may or may not help you.  Could there be a setting in your Video settings that could change the behavior of its handshake with the TV (I am grasping here....).  How about the Event Log?  Do you see anything in there about failed communication/authentication with the TV?

Is component an option? I know my 7800 and 8800 support it.

Dustin,

I have a very similar TV, the PZ77U.  I just build a HTPC.  It has the HDMI output built in.  I do not have the same problem you described.  However, I do have another annoying problem.  I have my desktop set to 1080P (1920x1080 @ 60Hz).  It display on my PZ77U but with a border around the entire desktop.  This border is maybe a 1/2 inch wide.  I do not see this border when I have my DirectTV HD receiver hooked up to the same HDMI input.  I have fooled around with different resolutions on my PC, but they all have this border.  Does anyone else see this border on their Panasonic plasma?  If not then it is probably the video card.

My setup:

Phenom II 905e
Gigabyte GA-MA785GPMT-UD2H (AMD 785G chipset)
Vista Ultimate 64 bit

Andrew Castillo

Yes, I get this boarder too - its most annoying. I have a Panasonic 42" plazma which is about 1.5 years old. My HTPC is a 5050e processor with a Gigabyte motherboard with onboard 780G (ATI HD3200) graphics connected via HDMI. The TV works great, but I have to say that I am not happy that my large 42" monitor is now a 41" monitor...

OK, not tried any of this, but found these web site which might be of help on the boarder issue:

http://www.xpmediacentre.com.au/community/video-audio-cards-windows-7/38173-black-border-panasonic-plasma.html

http://www.xpmediacentre.com.au/community/screens-projectors/28999-black-border-hdmi-input-panasonic-42pz700a.html

http://www.anandtech.com/showdoc.aspx?i=3609&cp=2

and specifically this from one of the sites above:

Fixed it! You were right - for some reason the ATI drivers had defaulted to 10% underscan, which was giving me the black border.

Here's how I fixed it (for anyone else who has a similar problem):

- Right click on desktop and select Catalyst Control Center (select Advanced mode) - Expand the DTV (HDMI) option - Click on "Scaling Options" - Drag the "Underscan/Overscan" slider all the way to the right (0%)

Now the picture fills the whole screen and pixels are small and crisp. Its amazing how much better it looks!

Check that you've got overscan disabled in the ATI Control Panel.  This is a slider bar that you can drag from 0% (no overscan) to 15%.

Basically older (CRT) monitors didn't show the very edge of the screen, so PCs sometimes output a black edge that would effectively be "off the screen" on the CRTs.  However, if you have a newer LCD/Plasma that has no overscan, you need to turn it off.

You may also need to ensure that your LCD/Plasma is set up for 1:1 pixel mapping, if it supports it.

Craig.

Damn, this came in whilst I was typing...!

Craig.

andrewcastillo:

This border is maybe a 1/2 inch wide.  I do not see this border when I have my DirectTV HD receiver hooked up to the same HDMI input.  I have fooled around with different resolutions on my PC, but they all have this border.  Does anyone else see this border on their Panasonic plasma?  If not then it is probably the video card.

I had this same border on my LCD when using my current ATI 3650 graphics card. If you have the Catalyst Control Center software installed, there is an option in there to zoom the display. Surprisingly, this was set to a 85% zoom to start with and I adjusted it to perfectly match the edge of the screen. I hope that the fix is as simple as this for you.

Brilliant! Worked for me!

I installed the latest Catalyst driver (version 9.8).  Unfortunately there is no zoom option.  My graphics card is HD4200 and I'm running Windows 7.  Does anyone know if this option is not enabled yet?

- Andrew

I have a panasonic 46 inch that gave me the same problem..I was using an ati 3450 I believe..It had about a 1inch border around the edge..I had an old Nvidia 9600 floating around through it in and Bam no border..So I threw the ATI card back in and installed the ati Catalyst driver 9.6  and it worked no border..It is something with that new version of Catalyst driver..Roll back a version and you should be all set..Or do what i did and go Nvidia..Although I have to say ATI does Blue-ray alot better.

 

 

-Fbearp

 I finally found the zoom setting in the 9.6 Catalyst driver.  It fixed the issue.  Now if I can only get the colors correct.  Thanks all for you help.

- Andrew

I've messed with over scan settings, applied a custom resolution and I still can not get anything to be 100% perfect. My problem is the entire pictures need to slide to the right. There is one or two lines on the right that are black and the left side is cut off. On a LCD or CRT monitor I know you can easily move the entire picture left to right (or up and down). Can a graphics card do this? If I enter my TVs service mode and move it I am afraid it will affect all inputs. My setup is 42" Panasonic TC-P42X1 an ATI 4350 and Win 7 Home Premium 64 bit. I got frustrated with the constant fiddling and downloaded

ATI Catalyst™ 10.1 Suite for Windows 7 (64 bit)

Now Catalyst isn't even working!