Archive for January, 2008

why?

Posted in Uncategorized on January 21, 2008 by makingthingswork

I spend a lot of time with technology, and usually things don’t work exactly right the first time.

I glean a lot of info off the web in various places in the process of getting things back in the ‘working’ category, and I figure I should give as well as I get.

So here we go.  I hope it helps.

Native resolution on my IN72

Posted in kevo, Linux, solved on January 21, 2008 by makingthingswork

My 4805 died a bit ago – threw a segment on the colorwheel, and that was it.

I found an IN72 on craigslist, and the price was right so I picked it up.

When I connected the DVI out on my mythtv box (aka the ‘kevo’), I got no love. No signal, nothing. This was strange since the 4805 worked fine, and they are basically the same.

I restarted xorg, and it came up ok, but it was at 720×480, not 848×480. I want to run native resolution if I can, so I spent the rest of the afternoon fighting with it.

After much troubleshooting the problems were:

the IN72 has a native resoltution of ~848×480, but it seems to report that it has a native resolution of 720×480 for some reason. Why they decided to do this, I have no idea.

Fortunately, the nvidia driver had an option to ignore the ‘native resolution’ setting.

I configured that, then found another problem. It couldn’t figure out the timing for the new mode for some reason. Internet to the rescue.

Here’s the nvidia config i ended up using:

Section "Device"
Identifier "nVidia Corporation NV34 [GeForce FX 5200]"
Driver "nvidia"
# some stuff omitted, not relevant
Option "ExactModeTimingsDVI" "true"
Option "ModeValidation" "NoDFPNativeResolutionCheck"
EndSection

And the modeline:

Section "Monitor"
Identifier "InFocus"
Modeline "848x480@60" 37.293 848 936 984 1104 480 508 509 563
EndSection

Some helpful commands:

## start Xwindows/xorg with verbose logging (logs to /var/log/Xorg.0.log):
startx -- -logverbose 6

Related error messages:
(WW) NVIDIA(0): Mode is rejected: Mode (848 x 480) is too large for DFP
(WW) NVIDIA(0): Native Resolution (Max: 720 x 480).

(WW) NVIDIA(0): Unable to use mode "848x480@60" for IFS InFocusIN72-D (DFP-0);
(WW) NVIDIA(0): cannot compute backend DFP timings (mode is larger than
(WW) NVIDIA(0): native backend 720 x 480).