no3d changes "something" more ...
fortunately 8.3 has ( undocumented ? ) nocompiz bootparameter
it gets parsed by /etc/X11/Xsession.d/45knoppix

however the "no3d" bug making x unstartable should be investigated ...

the error message with no3d is:
[ 40.424] vesa: Ignoring device with a bound kernel driver
Code:
[    40.404] (II) LoadModule: "vesa"
[    40.404] (II) Loading /usr/lib/xorg/modules/drivers/vesa_drv.so
[    40.404] (II) Module vesa: vendor="X.Org Foundation"
[    40.404]     compiled for 1.19.0, module version = 2.3.4
[    40.404]     Module class: X.Org Video Driver
[    40.404]     ABI class: X.Org Video Driver, version 23.0
[    40.404] (II) VESA: driver for VESA chipsets: vesa
[    40.424] vesa: Ignoring device with a bound kernel driver
[    40.424] (WW) Falling back to old probe method for vesa
[    40.424] (EE) Screen 0 deleted because of no matching config section.
[    40.424] (II) UnloadModule: "vesa"
[    40.424] (EE) Device(s) detected, but none match those in the config file.
the difference in xorg.conf is as follows:

Code:
knoppix@Microknoppix:~$ diff xorg.conf-mit-nocompiz  xorg.conf-mit-no3d
66c66
<     Option "Composite" "Enable"
---
>     Option "Composite" "Disable"
99c99,100
<     # Driver (chipset) autodetect
---
>         # Specified driver (chipset)
>     Driver      "vesa"
who knows why the kernel already allocated the device so vesa cancels itself ?
why at all nod3 writes vesa in the config ?

the followin scripts are also part of configuring x11 :
/sbin/hwsetup
/sbin/mkxorgconfig