How much graphics RAM is needed for playing1280x720 h264?

[mgh]

I use the latest RC build of vlc player for playing my mp4 files. For 640x480 encodes the cpu usage never crosses 3%. I encoded a clip to 1280x720 resolution. As soon as i tried playing it, the screen went blank and XP switched to safe mode telling me that the graphics had crashed. I have a PIV 2.4 GHz with on board AGP graphics set to 8 MB(max of the board).
I am posing the question because I feel that shortage of graphics RAM was the cause of the crash.

[Manao]

Well, it depends on the player. At least width x height x 3 / 2. But let's say your graphic card handles only RGB32 ( instead of 3/2, it's 4 ), and let's say your player tries to buffer one frame in the video card while displaying the previous one ( it doubles the needed video RAM, it's called double buffering ), then - in your case - you come very close your graphic card limitation. And if it does triple buffering, you lose.

But, before all that, what is your screen resolution, are you trying to play it back fullscreen, and have you tried with another player ?

[DarkZell666]

I had a similar problem with an onboard Intel Graphics IGP for some clips. I installed some other drivers for it, and the crash part of the problem was solved. Try encoding at resolutions inferior or equal to your desktop resolution (it's only a temporary solution to another problem but ...).

I personnally can't playback videos bigger than 1024*y with mplayer, so I need to add the "-vf scale=1024:576" option so the player downscales the picture before it's sent to the graphics card.

You can do the same with VLC in the preferences (but I couldn't tell you where though :p).

[mgh]

A 1024x768 encode plays perfectly in vlc player with my screen res at 800x600-all other players it is like a slide show. 640x480 plays on all players.
As suggested,tried removing triple buffering, also tried using system memory instead of graphics memory in vlc and tried 1280x960 screen resolution.
The error i get is
the ialmrnt5 display driver has stopped working normally
I got the same error when trying to load the 1280x720 mp4 in virtualdub mod via avisynth. When I added a resizing to 640x480 to the script-the PC simply rebooted.
I think that i should not go beyond 1024x768 resolution.
Thanx for the inputs

[mgh]

DarkZell666
as per your suggestion-i downloaded latest graphics driver from intel for my board and installed. No crash for the 1260x720 video even full screen-little stuttering maybe-cpu maxs out. The 1048x768 video plays on other players with mild stuttering, the 1260x720 video stutters more, the cpu maxs out.
:D :thanks:

[DarkZell666]

Haha, it worked out better for you than for me then :p

Nice to hear it worked, specially with 8MB of VRAM :)