8400GS to 1080p LCD TV

mathog · 11-23-09, 12:40 PM

Our mythtv box currently uses component out to an analog CRT with VDPAU, and it all works great - except the TV is now crapping out (it is acting like it has cracked solder somewhere). So we're going to buy a 1080p LCD to replace it. The question is, with a 256M 8400GS card, what would be the best way to hook the MythTV box to the new TV? I'm looking for the highest resolution where the VDPAU will still work. (If VDPAU is off the MythTV EPG and other menu systems becomes unusable with live TV.) Mostly the new TV will be used to watch over the air TV or standard DVDs. However, it would be nice with the higher display resolution to be able to use it as a computer too.

I'm sure the existing component cables will work, and the xorg resolution can be raised from the current 640 x 480 (not sure how far though with this card). However, there is also a DVI output on the card which is currently unused. Would it be better to get a DVI to HDMI cable and go that way instead? There is a VGA connector on the card, possibly not on the TV though. Is that worth looking at, or just stick with DVI or component?

Thanks.

Lost Dog · 11-23-09, 02:39 PM

I was in the exact same situation as you but I have the 512mb 8400.

I got rid of my old RPTV and went with a Toshiba 55SV670u (KILLER television). I use a DVI to hdmi converter at the video card and feed the TV with hdmi. I could not be happier with the picture. It's quite an incredible change over my old set.

mathog · 11-23-09, 03:34 PM

Quote:

Originally Posted by Lost Dog

I got rid of my old RPTV and went with a Toshiba 55SV670u (KILLER television).

If I spent that much the wife would kill ME.

Quote:

Originally Posted by Lost Dog

I use a DVI to hdmi converter at the video card and feed the TV with hdmi.

In the interest of not reinventing the wheel...

Is the DVI->HDMI converter at the card then HDMI->HDMI cable to the TV better somehow than using a single DVI to HDMI cable?
What does your xorg.conf look like? (This will be the only display device attached on mine.)
VDPAU works in that mode?

Thanks.

Lost Dog · 11-23-09, 09:43 PM

I chose to go with a HDMI -> HDMI cable because at this point for home theater DVI is no longer used. All my video wiring is in-wall so I only wanted to run it once! Down the road I didn't want to have to replace a DVI -> HDMI. The converter was only a few bucks from monoprice and works great.

Here is my xorg.conf:

Code:

# nvidia-xconfig: X configuration file generated by nvidia-xconfig
# nvidia-xconfig:  version 1.0  (buildmeister@builder62)  Wed May 27 01:58:49 PD
T 2009


Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0" 0 0
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
EndSection

Section "Files"
EndSection

Section "Module"
    Load           "dbe"
    Load           "extmod"
    Load           "type1"
    Load           "freetype"
    Load           "glx"
EndSection

Section "InputDevice"

    # generated from default
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/psaux"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"

    # generated from default
    Identifier     "Keyboard0"
    Driver         "kbd"
EndSection

Section "Monitor"
   Identifier     "Monitor0"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
EndSection

Section "Screen"

    Identifier     "Screen0"
    Device         "Device0"
    Option         "ConnectedMonitor" "DFP-0"
    Option         "CustomEDID" "DFP-0:/etc/X11/55SV670u.edid"
    Option         "ModeValidation" "NoVertRefreshCheck,NoHorizSyncCheck"
    Monitor        "Monitor0"
    DefaultDepth    24
    Option         "DPI" "100 x 100"
    Option         "NoLogo" "True"
    Option         "CoolBits" "1"
    Option         "UseEvents" "False"
    SubSection     "Display"
        Modes      "nvidia-auto-select"
        Depth       24
    EndSubSection
EndSection

Section "Extensions"
    Option         "Composite" "Disable"
EndSection

The only thing non-standard that I did was export the TV's EDID and then call it from the xorg.conf. That way if the TV is unplugged or something it still will set everything up correctly.

VDPAU works great. No issues going 1080i to 1080p. I don't use anything to switch display modes or refresh rates. I don't watch bluray and I'm not sure if there is any benefit to doing that with dvd.

mathog · 11-24-09, 11:02 AM

Quote:

Originally Posted by Lost Dog

Here is my xorg.conf:

Code:

#much deleted...

Section "Screen"

    Identifier     "Screen0"
    Device         "Device0"
    Option         "ConnectedMonitor" "DFP-0"
    Option         "CustomEDID" "DFP-0:/etc/X11/55SV670u.edid"
    Option         "ModeValidation" "NoVertRefreshCheck,NoHorizSyncCheck"
    Monitor        "Monitor0"
    DefaultDepth    24
    Option         "DPI" "100 x 100"
    Option         "NoLogo" "True"
    Option         "CoolBits" "1"
    Option         "UseEvents" "False"
    SubSection     "Display"
        Modes      "nvidia-auto-select"
        Depth       24
    EndSubSection
EndSection

Section "Extensions"
    Option         "Composite" "Disable"
EndSection

The only thing non-standard that I did was export the TV's EDID and then call it from the xorg.conf. That way if the TV is unplugged or something it still will set everything up correctly.

What command did you use to obtain and save the TV's edid?
xorg.conf is letting the driver pick a mode, which one is it actually using?

Thanks

mathog · 12-05-09, 07:28 PM

Quote:

Originally Posted by mathog

What command did you use to obtain and save the TV's edid?

Found it - nvidia-settings, then click on the DFP-0 device, and there is a save edid option.

One major problem with the DVI->HDMI conversion is that there is some confusion between the EDID the TV supplies and what the nvidia driver does with it. This results in somehow or other the driver telling the TV that it should look for sound on the HDMI cable, and since that comes from a DVI, which didn't have sound, there is no there there. Worse, this overrides the real analog input on the specified "DVI Audio In" jacks. Luckily this problem has been solved by others before, although you would never find that out from Samsung's PATHETIC phone in customer service. They could not tell me what was wrong, but I later found a technical note describing exactly this problem on their web site!

The fix for the sound problem is this:

1. save the edid using nvidia-settings
2. download edid_disable_exts from analogbits.com, build it.
3. edid_disable_exts original.edid new.edid
This chops off any extension blocks and recalculates the checksum.
4. mv new.edid /etc/X11/tvname.edid
5. edit /etc/X11/xorg.conf as in lostdog's example, to read the edid
6. restart the X11 server (ctrl-alt-backspace)

Voila, sound works!

jpterj · 12-07-09, 09:14 AM

Quote:

Originally Posted by mathog

Found it - nvidia-settings, then click on the DFP-0 device, and there is a save edid option.

One major problem with the DVI->HDMI conversion is that there is some confusion between the EDID the TV supplies and what the nvidia driver does with it. This results in somehow or other the driver telling the TV that it should look for sound on the HDMI cable, and since that comes from a DVI, which didn't have sound, there is no there there. Worse, this overrides the real analog input on the specified "DVI Audio In" jacks. Luckily this problem has been solved by others before, although you would never find that out from Samsung's PATHETIC phone in customer service. They could not tell me what was wrong, but I later found a technical note describing exactly this problem on their web site!

The fix for the sound problem is this:

1. save the edid using nvidia-settings
2. download edid_disable_exts from analogbits.com, build it.
3. edid_disable_exts original.edid new.edid
This chops off any extension blocks and recalculates the checksum.
4. mv new.edid /etc/X11/tvname.edid
5. edit /etc/X11/xorg.conf as in lostdog's example, to read the edid
6. restart the X11 server (ctrl-alt-backspace)

Voila, sound works!

Well a DVI->HDMI converter does/may carry sound if the video card has an SPDIF pass-trough connector. I have only experience from an 8600 card but that worked perfectly with DVI->HDMI.

Do you have this pass-trough connector on your video card and correponding output on your motherboard or soundcard?

mathog · 12-07-09, 11:08 AM

Quote:

Originally Posted by jpterj

Do you have this pass-trough connector on your video card and correponding output on your motherboard or soundcard?

I do not believe the video card, an ASUS EN8400GS, has this ability:

http://www.newegg.com/Product/Produc...82E16814121240

jpterj · 12-07-09, 11:59 AM

Quote:

Originally Posted by mathog

I do not believe the video card, an ASUS EN8400GS, has this ability:

http://www.newegg.com/Product/Produc...82E16814121240

This customer review seems to indicate that it does: http://www.newegg.com/Product/Produc...82E16814121240, search for SPDIF.

There should be a two pin header on the card if it supports this.

mathog · 12-07-09, 06:09 PM

Quote:

Originally Posted by jpterj

This customer review seems to indicate that it does: http://www.newegg.com/Product/Produc...82E16814121240, search for SPDIF.

There should be a two pin header on the card if it supports this.

Well, I'm not entirely sure that review is for this card, since in the same paragraph it refers to a 9600GT. The specifications for the card don't say anything about S/PDIF, and the pictures on Newegg don't show a header, although there is a place on the circuit board for one.

Anyway, I have the analog sound working now, and it is good enough.

k00zmi4 · 01-16-10, 10:55 AM

Quote:

Originally Posted by mathog

Well, I'm not entirely sure that review is for this card, since in the same paragraph it refers to a 9600GT. The specifications for the card don't say anything about S/PDIF, and the pictures on Newegg don't show a header, although there is a place on the circuit board for one.

Anyway, I have the analog sound working now, and it is good enough.

Well, if you're still interested in digital, here's a closer look:
Though I must admit 8400gs lacks a little power with 1080@24p output. Eventually, I'm stuck with software (using C2D E8500 CPU) decoding of high def contents like that, since it's the only way I don't get stuttering issues.

11-23-09, 12:40 PM	#1
mathog Registered User Join Date: May 2006 Posts: 90	8400GS to 1080p LCD TV Our mythtv box currently uses component out to an analog CRT with VDPAU, and it all works great - except the TV is now crapping out (it is acting like it has cracked solder somewhere). So we're going to buy a 1080p LCD to replace it. The question is, with a 256M 8400GS card, what would be the best way to hook the MythTV box to the new TV? I'm looking for the highest resolution where the VDPAU will still work. (If VDPAU is off the MythTV EPG and other menu systems becomes unusable with live TV.) Mostly the new TV will be used to watch over the air TV or standard DVDs. However, it would be nice with the higher display resolution to be able to use it as a computer too. I'm sure the existing component cables will work, and the xorg resolution can be raised from the current 640 x 480 (not sure how far though with this card). However, there is also a DVI output on the card which is currently unused. Would it be better to get a DVI to HDMI cable and go that way instead? There is a VGA connector on the card, possibly not on the TV though. Is that worth looking at, or just stick with DVI or component? Thanks.

11-23-09, 02:39 PM	#2
Lost Dog Registered User Join Date: Aug 2007 Posts: 151	Re: 8400GS to 1080p LCD TV I was in the exact same situation as you but I have the 512mb 8400. I got rid of my old RPTV and went with a Toshiba 55SV670u (KILLER television). I use a DVI to hdmi converter at the video card and feed the TV with hdmi. I could not be happier with the picture. It's quite an incredible change over my old set.