The VideoLAN Forums

I recently upgraded from a 7900GTX to an 8800GTS G92 512mb.

On my old card i could watch my videos on my secondary display with no problems. Now that Ive upgraded Whenever i put the video playback into the secondary screen it stops video playback altogether, but keeps playing on audio. I have the second display set up on nVidia "Dualview" so that its basically just extra space, not a horizontal sweep or mirror image. All my windowed games work on the other screen so i know that port isnt dead or anything. Only VLC stops working on the second display.

VLC has a similar problem with "external" or "secondary" displays -- eg, if I attach my laptop via S-VIDEO to a regular TV (after the laptop is already booted to WinXP, and VLC is playing a video) and then hit the old Fn+F4 key to switch to the external monitor, then VLC continues playing the sound WITHOUT VIDEO ... just a black screen. Stopping and starting the video again solves the display problem.

This problem has existed for many months, but it's such an obvious problem I expected it was reported frequently and would be sorted out in the next release. Since it's still there, and there are other problems with multiple displays, perhaps no one has noticed, yet ?!?

For the nth time, just deactivate the Overlay, because this is more than probable that you graphic card doesn't accelerate both monitors.

For the nth time, just deactivate the Overlay, because this is more than probable that you graphic card doesn't accelerate both monitors.

Wow, should that really be so obvious? Maybe if it's come up for the nth time, then the default configuration is not quite helpful ... or maybe there's really a bug in VLC somewhere.

I have an ATI Mobility Radeon Xpress 200 -- yeah, not so new, but not so old, either. I've updated drivers to the latest ATI/AMD Catalyst drivers/utilities. The "overlay" setting for this adapter claims "The overlay controls are automatically activated during playback of any video file type that supports overlay adjustments." and gives a few options for "dual-controller" mode -- clone to an external monitor.

So by all appearances, VLC's "Overlay video output" option should not cause such problems on my system.

Not only does the overlay option cause problems, but even if I disable "overlay video output", the video still disappears (audio never disappears) when switching between monitors (Fn+f4)

Fn+f4 or any hotkeys that are laptop related can cause problems, because you shouldn't change default display while you play video.

Fn+f4 or any hotkeys that are laptop related can cause problems, because you shouldn't change default display while you play video.

No disrespect intended, but I think you mean to state that "you shouldn't change default display when using VLC, because we haven't considered this possibility." Yet ?!?

In fact, VirtualDub -- developed by a single individual AFAIK -- handles such changes seamlessly, so switching monitors is certainly detectable behavior that software can/should adapt to; it simply needs to be handled properly ... like any situation. To me, failure to handle a monitor switch properly is a bug in the software.

Unlike, say, expecting VLC to make me some savory popcorn during the opening credits. Now that's an unrealistic expectation

Have you tried all the video output modules (DirectX, OpenGL and Direct3D)?

Yeah I have tried switching output modules and disabling overlay. Neither worked. Like i said before, I had no problem with the same drivers on my 7900GTX and now i am having problems with my 8800GTS 512.

169.21 WHQL driver set
BFG 8800GTS (G92) 512mb 675mhz

For the nth time, just deactivate the Overlay, because this is more than probable that you graphic card doesn't accelerate both monitors.

This is not the case with my computer. I know this because if it were I wouldnt be able to play hardware accellerated games on my secondary screen as stated in my original post

Overlay hardware is different than other accelerations in display adapter. For example you can run multiple 3D games at the same time but you can only have one Overlay mapping at time. (there are certain cards that support multiple Overlays, but AFAIK not in consumer markets)
EDIT:
And I almost forgot. With Vista or if you are using Geforce 8000 series or newer NVIDIA cards, Full-screen video mirror doesn't work. That is said on Driver release notes
http://us.download.nvidia.com/Windows/1 ... _Guide.pdf

ok well thanks for clarifying, but I'm running on Windows XP and im not using mirror mode or setting the player to fullscreen when im putting it on the secondary display. I just keep it windowed and off to the side while i do my work in other windows

Found a solution! Finally tried out some different output modules than i tried before. Got it to run fine on the OpenGL module. Doesnt seem to work on DX, D3D, or a few others, but works great under OGL

I discovered after buying a couple of nvidia cards that they will not display some types of video on the second output. I had to dig into nvidia's forums to find the information, they don't tell you up front but it just won't work. I sent them back and bought ATI cards and everything works as it should.

I just wanted to say thanks guys for this post, I mean i really don't know what overlay is and all, but it correct my problems. Thanks again guys. Not to sound 'less intelligent' and all, but if someone could explain what overlay is, that would be great. (does it have to do with post processing or something)?

http://en.wikipedia.org/wiki/Hardware_overlay
that hopefully explains how video overlay works.

hello
not just to up a post but i confirme with nvidia card it's not work when vlc is in D3D mode ...
put the open gl and it works fine

thank for the info