Problem during session closing

[Benjamin Klein-Fignier <bklein phoenix linux esiea fr>]

I'm installing Linux on 66 Intel-Celeron 466Mhz 128Mo RAM Video Card Riva
TNT 16Mo with Xfree 3.3.3.1 and kernel 2.2.10. The distribution I'm
installing is Mandrake 6.0 with Gnome.
When I close a Gnome session, a special effect fades the screen
before going back to GDM. This effect is amazingly SLOW !!
I made an image of the installation and put it on a Pentium 200 64Mo RAM
Video Card Matrox Mystic 4Mo. The special effect is perfectly smooth !!!
WHY ???
It is the same installation, same programs, same X server (XF86_SVGA) !
Does someone know why ? And how to correct this problem ???

Thanks for your help

Ben.

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  /\_/\    Benjamin Klein-Fignier
 ( o o )   aka "FENNEC" NEWSMASTER @ ESIEA
  \   /    Ecole Superieur d'Informatique Electronique Automatique
  /\ /\    bklein@alpha.esiea.fr / bklein@phoenix.linux.esiea.fr
 |  °  |   ICQ# 40123319
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