I´ve set up a dual display / Presentation only setup with C40 and 2 Samsung 460DX-3 LFD-Displays. From C40 view, HDMI1 is connected to the First Display and DVI2 ist connected to the second Display (set to "Presentation only" and Resolution "Auto"). My Notebook (HP Compac 8510p) is connected to DVI3.
When I connect my PC to the C40, the resolution is set to my native PC resolution 1280x800 , but the C40 sends 1920x1080 /60 to the presentation display.
The result ist, that the content is shown too small with black borders around it.
So the C40 doesn´t use the PC resolution to send the presentation to the content Display. Additionally, the content display doesn´t work at all after a reset of C40 (i have to reconfigure it first to Dual Monitor an afterwards to Presentation only).
When i connect my PC directly to the Samsung Display, everything works fine and the Samsung displays my PC desktop in fullscreen with the correct resolution: 1280x800
You can try to set the C40 to stretch the image to fill out the black space.
xConfiguration Video Layout ScaleToFrame:
Default is MaintainAspectRatio...
Or you can try to change the resolution on the DVI output.(but one would like the codec to use the highest resoloution against the monitor.)
xConfiguration Video Output DVI  Resolution:
However, 1280x800 doesn't look like a resolution that is native to the C40!
Yes - I´ve tried these settings without any success.
Layout ScaleToFrame seems so primary set the streching for the content stream.
Setting Video Output to a fixed resolution only works well, if the PC is set to the same resolution manually - i think the users will not be able to handle this.
It seems, that 1280x800 is native on C40, because otherwise the PC wouldn´t negotiate this with C40 using EDID. For example Cisco CTS only supports 1024x768 and if I connect my PC to it, it will switch to this resolution automaticly because of EDID negotiation.
Streching the image wouldn´t be the solution, because the native resolution is lost. The main reason of buying professional display instead of LCD-TVs was because of the 10x better experience by display the content with a native resolution.
Additionally, I recognized, that the presentation display doesn´t work anymore after a reset.
Does anybody has the same issue?
What I meant was that C40 will not use 1280x800 on the outputs. It's possible that it will negotiate that resolution on the input. Have you tried to force some more common resolutions on your PC to see if the AUTO setting for the output will change accordingly?
I don't understand what you mean with "the presentation display doesn't work anymore after a reset"? Is it the display that stop working or something with the C40 codec?
yes - that´s what I meant, too. C40 uses 1280x800 only on the input, but not on the output.
When I restart the C40, it doesn´t send the presentation to the presentation display anymore. The Display recognizes input with 1920x1080 from C40, but the C40 doesn´t send the contenct itself to the display - so the display keeps black. To solve this, I have to configure the C40 to dual display, share a presentation and set the C40 back to Presentation-only mode.
If i remember correctly, If I change the input resolution on PC, the presentation display shows thie picture accordingly to the resolution size within the 1920x1080-picture: higher Resolution=bigger Picture, smaller Resolution=smaller Picture.
Generally, 1280x800 seems to be a common resolution on HP Notebooks. I´m wondering why C40 supports different resolutions on inputs and outputs, because if C40 doesn´t support a specific output resolution, it makes no sense to set this on input via EDID.
I've had this problem too. It was the cable being used between the laptop and the CODEC. It did not send the correct signal to the CODEC.
Are you using the Cisco cable that comes with the system? Or a third party cable?
Given that the thread you're replying to is over 2 years old, it's likely that the OP has resolved their issue by now. The codec would have been on TC version 3 or lower at that stage (TC6.2 is the currently released version).
In general, I set the output on the codec to match the display that is connected and let the codec do any required scaling. So if the display connected does 1920x1080/60, I set the output on the codec to that.