915GM Xorg with dualhead problems

David Rogal theirpuppet at yahoo.com
Wed Nov 30 14:48:03 GMT 2005

Hello All,

I'm having a similar problem specified in: 

X works just fine on a single monitor. When I start messing around with the
xorg.conf and try to go dualhead, I get either only one head working with a
single desktop or one head working with two desktops splitting the screen or X
just bombs. To further elaborate on the 'split screen' result; imagine the
screen's real estate split into 4 equal parts (a 2x2 square), with only the top
2 in use both as clones of each other. That's what I've seen, on both monitors
(however, only one at a time - meaning that occassionaly I have video only on
the CRT while the laptop's LCD turns off).

Each and every time I go for dualhead, I get the /dev/agpgart warning/error and
VideoRAM errors.

Compaq nc6120 laptop
6.0-STABLE #0: Tue Nov 29 13:39:18 GMT 2005
Intel Corporation Mobile 915GM Express Graphics Controller on PCI:0:2:0 (and
apparently also at PCI:0:2:1, though this can cause weirdness)
xorg-server- (ports/x11-servers/xorg-server-snap cvsup'ed and
compiled a few hours ago)

# cat /boot/loader.conf
# grep agp /usr/src/sys/i386/conf/GENERIC
device    agp    # support several AGP chipsets
# kldstat
Id Refs Address Size Name
1 3 0xc0400000 63590c kernel
2 1 0xc0a36000 58558 acpi.ko

I've attached the xorg.conf and /var/log/Xorg.0.log for each of the following
Test 1 - Both BusID's the same. X failed to start. - AddScreen/ScreenInit
Test 2 - BusID's different. complete loss of video on the laptop. no response
ever with CRT.
Test 3 - Xorg -configure output.

I've worked so long on this, changing settings and getting weird results.
Please help. This is a work box and if I can get dual head on it, I will be so
much better off.

Anything more you need, please let me know. I suspect the problem is related
# ls -l /dev/agpgart
ls: /dev/agpgart: No such file or directory

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