[lug] XFree86 4.1.0 slow compared to 3.3.6?

[Tkil]

my box got hacked this weekend, so i took the opportunity to upgrade
to the latest and greatest KRUD (2001-11).  most things are working
happily, but i've noticed that many things in X seem *much* slower
than before.  i don't have hard numbers handy, but things like
graphics scrolling (as in mozilla) and even just moving whole windows
(i use fvwm2, so i just move an outline -- but the repainting of the
window in the new location is noticably slow) are both much slower.

any ideas?  the video hardware hasn't changed: it's a matrox G200 AGP
card (16MB memory, i think).  i'm using the same resolution (a rather
odd 1360x1024, closer to 4:3 than 1280x1024 is) as before, same
monitor, and same mode line for that matter.

i have a few hypotheses, but i don't have a good way of checking them
out offhand:

1. the new X server isn't set up for acceleration properly.

2. i'm using the frame buffer x server, not the one specifically for
   my card.

3. the kernel (2.4.9-7) is slowing things down somehow (AGP not set up
   correctly, DRI weirdness, who knows).

4. the new X is much more sensitive to screen size than before, and
   can only accellerate on the 256 block boundaries.

5. screen depth of 24 is causing issues; maybe i should try 32 again.

does anyone have other suggestions?  it's not too bad yet, but it is
slow enough to be very noticable.

thanks,
t.