Bug#390203: problem lies with xserver-xorg-mga-1.2.1.3

[Alex Winbow <awinbow@panix.com>]

Same problem with a G400. 1600x1200 worked before, but after upgrading to 
xserver-xorg-video-mga_1.2.1.3.dfsg.1-2, nothing above 1152x864 worked. No 
pertinent error messages (that I could see) in the logfile, and the 
monitor goes into DPMS standby mode. Ctrl-alt-backspace restores the 
terminal.

Same behavior as if, in the old days, a misconfigured X modeline tried to 
drive the monitor at too high a frequency. Which is odd, because my 
Viewsonic GS790 is capable of 1600x1200 at least.

Downgrading to xserver-xorg-video-mga_1.4.1.dfsg.1-4 by hand restored 
video.

Alex Winbow