I recently upgraded xorg on my workstation at the office. Immediately I started seeing problems with one of the monitors. It would go empty/blank/black for three seconds, then resume normal operation. Then it would go blank again when I interacted with the screen. In short, that one monitor was completely useless.
Swapping cables […]

This is the /var/log/Xorg.0.log for my RadeonHD.

X.Org X Server 1.7.5
Release Date: 2010-02-16
X Protocol Version 11, Revision 0
Build Operating System: FreeBSD 8.1-STABLE amd64
Current Operating System: FreeBSD subie.example.com 8.1-STABLE FreeBSD 8.1-STABLE #1: Wed Aug 11 14:34:19 EDT 2010 dlangille@subie.example.com:/usr/obj/usr/src/sys/DVL amd64
Build Date: 12 August 2010 05:57:37PM

Current version of pixman: 0.16.6
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This is the xorg.conf file for my RadeonHD setupt

Section “ServerLayout”
Option “AllowEmptyInput” “off”
Identifier “X.org Configured”
Screen 0 “Screen0″ 0 0
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