This is for a Debian/Squeeze new install. It's a 6 headed system 3 wide, 2 high, using three Radeon 7000/VE PCI video boards. Why does the center two heads work, all video come up, but the left and right heads have video tearing/striping. I can pop up an xterm and it will look right, but will be subject to the same tearing when I move to other heads. The mouse moves properly between all heads. Problem occurs with both GNOME and KDE (in the same way). [cerberus, /var/log] # uname -a Linux cerberus 2.6.32-5-686 #1 SMP Mon Jan 16 16:04:25 UTC 2012 i686 GNU/Linux [cerberus, /var/log] # lspci 00:00.0 Host bridge: Intel Corporation 82865G/PE/P DRAM Controller/Host-Hub Interface (rev 02) 00:02.0 Display controller: Intel Corporation 82865G Integrated Graphics Controller (rev 02) 00:06.0 System peripheral: Intel Corporation 82865G/PE/P Processor to I/O Memory Interface (rev 02) 00:1d.0 USB Controller: Intel Corporation 82801EB/ER (ICH5/ICH5R) USB UHCI Controller #1 (rev 02) 00:1d.1 USB Controller: Intel Corporation 82801EB/ER (ICH5/ICH5R) USB UHCI Controller #2 (rev 02) 00:1d.2 USB Controller: Intel Corporation 82801EB/ER (ICH5/ICH5R) USB UHCI Controller #3 (rev 02) 00:1d.3 USB Controller: Intel Corporation 82801EB/ER (ICH5/ICH5R) USB UHCI Controller #4 (rev 02) 00:1d.7 USB Controller: Intel Corporation 82801EB/ER (ICH5/ICH5R) USB2 EHCI Controller (rev 02) 00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev c2) 00:1f.0 ISA bridge: Intel Corporation 82801EB/ER (ICH5/ICH5R) LPC Interface Bridge (rev 02) 00:1f.1 IDE interface: Intel Corporation 82801EB/ER (ICH5/ICH5R) IDE Controller (rev 02) 00:1f.2 IDE interface: Intel Corporation 82801EB (ICH5) SATA Controller (rev 02) 00:1f.3 SMBus: Intel Corporation 82801EB/ER (ICH5/ICH5R) SMBus Controller (rev 02) 00:1f.5 Multimedia audio controller: Intel Corporation 82801EB/ER (ICH5/ICH5R) AC'97 Audio Controller (rev 02) 01:00.0 VGA compatible controller: ATI Technologies Inc Radeon RV100 QY [Radeon 7000/VE] 01:01.0 VGA compatible controller: ATI Technologies Inc Radeon RV100 QY [Radeon 7000/VE] 01:02.0 VGA compatible controller: ATI Technologies Inc Radeon RV100 QY [Radeon 7000/VE] 01:08.0 Ethernet controller: Intel Corporation 82562EZ 10/100 Ethernet Controller (rev 02)