I have a display capable of 1280x1024. I'm working on a map project, and wanted to have as big virtual screen as possible. So, I put "Virtual 2304 1728" into the screen section of xorg.conf. My card is a Matrox G400 and this is an average Pentium III class machine. I've noticed I am unable to get bigger virtual screen than 2048 x 2048 = 4 194 304 pixels. Otherwise parts of the screen get overlaid (painted twice) and X soon crashes. Is there any way around this? I have 32MB video memory, and that should be enough for another 4 million pixels of virtual desktop real estate.
This isn't the right place for a question like this (and I don't know the answer :P). You should either post a message to the xorg mailing list or file a bug at https://bugs.freedesktop.org. If you end up filing a bug, please post the link here in case this is something that gets fixed upstream.
Link to corresponding Freedesktop bug: https://bugs.freedesktop.org/show_bug.cgi?id=7033
Thanks :)