195.36.24: No Signal on Displayport

MeisterP · 06-10-10, 02:02 PM

Hello,

I try to connect an external monitor with a Displayport to DVI-D (Dual Link) cable. The graphical nvidia-settings tool recognizes the external monitor and I'm able to set up all options but after restarting X, the second monitor doesn't receive a signal. It's like everything is working (X starts, no errors, no segfault, I can move the mouse out off the laptop screen... ) just that the signal gets lost somewhere in the graphic card or in the adapter.

If I connect via VGA the external monitor works just fine.

I am running Fedora 13 on a HP Elitebook 8540w, the graphic card is a Quadro FX 880M.

Kernel: 2.6.33.5-112.fc13.x86_64
Driver: 195.36.24

Working configuration with VGA --> nvidia-bug-report.vga.log.gz
No Signal found with DP-DVI --> nvidia-bug-report.dp-dvi.log.gz

Any help would be appreciated. Thanks.

DanM · 06-11-10, 12:38 AM

Same issus here with a Quadro FX 3800.

**danix** · 06-11-10, 03:25 PM

DisplayPort to dual link DVI adapters are active devices; you might be seeing and configuring the adapter in the control panel, and the adapter may be failing to bring up the display. Have you tried a single link passive dongle?

MeisterP · 06-12-10, 01:33 PM

Hey Danix,

Thanks for your reply.

The adapter I use is not an active one. The DVI plug has all the pins like a dual link adapter (according to Wikipedia http://en.wikipedia.org/wiki/Digital_Visual_Interface) but apparently not all of them are really used.
To make it short, I already used a DisplayPort to DVI-D (Single Link) adapter - the information in my initial post is wrong. Sorry about that.

But more important, I was able to get the second monitor up and running via DisplayPort. The problem was that I patched the kmod-nvidia from rpmfusion. The patch solves a problem with Intel-VT enabled and can be found here: http://www.nvnews.net/vbulletin/showthread.php?t=151791

After installing the original driver from rpmfusion and readding iommu=soft to the kernel boot line the DisplayPort works fine.

The patch solved the vt-iommu issue but it seems to break the DisplayPort. I think the problem is either the patch or the way I applied it to the package.

If you need more information feel free to ask.

**danix** · 06-14-10, 12:49 PM

Thanks for the update. I'll investigate for possible interactions between the Intel-VT patch and DisplayPort functionality.

06-11-10, 12:38 AM	#2
DanM Registered User Join Date: Jun 2010 Posts: 4	Re: 195.36.24: No Signal on Displayport Same issus here with a Quadro FX 3800.

06-11-10, 03:25 PM	#3
danix NVIDIA Corporation Join Date: Feb 2010 Location: Santa Clara, CA Posts: 237	Re: 195.36.24: No Signal on Displayport DisplayPort to dual link DVI adapters are active devices; you might be seeing and configuring the adapter in the control panel, and the adapter may be failing to bring up the display. Have you tried a single link passive dongle?

06-12-10, 01:33 PM	#4
MeisterP Registered User Join Date: Jun 2010 Posts: 6	Re: 195.36.24: No Signal on Displayport Hey Danix, Thanks for your reply. The adapter I use is not an active one. The DVI plug has all the pins like a dual link adapter (according to Wikipedia http://en.wikipedia.org/wiki/Digital_Visual_Interface) but apparently not all of them are really used. To make it short, I already used a DisplayPort to DVI-D (Single Link) adapter - the information in my initial post is wrong. Sorry about that. But more important, I was able to get the second monitor up and running via DisplayPort. The problem was that I patched the kmod-nvidia from rpmfusion. The patch solves a problem with Intel-VT enabled and can be found here: http://www.nvnews.net/vbulletin/showthread.php?t=151791 After installing the original driver from rpmfusion and readding iommu=soft to the kernel boot line the DisplayPort works fine. The patch solved the vt-iommu issue but it seems to break the DisplayPort. I think the problem is either the patch or the way I applied it to the package. If you need more information feel free to ask.

06-14-10, 12:49 PM	#5
danix NVIDIA Corporation Join Date: Feb 2010 Location: Santa Clara, CA Posts: 237	Re: 195.36.24: No Signal on Displayport Thanks for the update. I'll investigate for possible interactions between the Intel-VT patch and DisplayPort functionality.