I did some experiments on my Fujitsu A6030. The default xorg.conf
contains a line Driver "i810", I changed it to "i915" and reboot (I have
to that a reboot if I don't want to blank screen after logout),
then I hit (Failed to Load Kernel Module "i915") problem.
After let the xserver to switch the default xorg.conf,
the file /var/log/Xorg.0.log tells me that it loads "i810"
via Loading /usr/lib64/xorg/modules/drivers/i810_drv.so.
I checked /usr/lib64/xorg/modules/drivers does not contain i915_drv.so,
so I guess this is the crux of the problem. Can it be a problem that
the 64-bit driver is not compiled properly ??
I may try a 32-bit centos5.1 to confirm my theory.
BTW, I found a related thread in this forum: