On Wed, Jan 10, 2007 at 03:46:59PM +0100, Jonathan Thornburg wrote: > The built-in LCD display works fine at 1600x1200. > My problem is that I can't get external video output properly. There > seem to be two cases (neither one of which fits my definition of "properly"): > * If, in the BIOS setup, I set "Boot Display Device" to "LCD", then > I can get 1600x1200 VGA output when booting and before I start X, > but I get no external video output at all once I start X. > * If, in the BIOS setup, I set "Boot Display Device" to "VGA+LCD" or > "VGA+DVI+LCD", then I get no external video output when booting and > before I start X, but when I start X I get only 640x480 resolution > (and matching external video output).
I'm not sure exactly when, but at some point something appears to have changed, presumably in X, since X now seems to use 640x480 whenever it's unsure about the output device (previously I'm fairly sure it always used whatever resolution you told it to). That seems to be coupled with the fact that my T43 (which I know has a different graphics card from your T43p, but there again you seem to be having the same problems) plays funny buggers with the external output. On a handful of data projectors, I've got the correct 1024x768; on most I get 640x480; and I get occasional oddities like "clipped" 1024x768 (missing 20-30 pixels on all edges). Nothing I've tried thus far has persuaded X to use a sensible resolution in such cases. Laurie -- http://tratt.net/laurie/ -- Personal http://convergepl.org/ -- The Converge programming language http://sosym.dcs.kcl.ac.uk/ -- Software and Systems Modelling Team
