[ltp] glxgears on a T42 (Fedora Core 3) with ATI Mobility Radon 7500

[Jed Diem]

Folks,

I'm  running Fedora Core 3 on a T42 (2373K1U) using  the 
2.6.10-1.770_FC3 with Core 3 packages up-to-date.  The graphics chip is 
the ATI Mobility Radon 7500 at 1023x768.  I use either Gnome or Xfce.

glxgears runs at about 500 fps but the screen output is slow, i.e. the 
gears turn slowly.  Except, when  I move the terminal window from which 
I started glxgears so that it partially covers the glxgears output 
window, the gears start turning very fast and the frame rate works it 
way up 950 fps.  Move the terminal off of the glxgears output window and 
the slowly turning gears reappear and the frame drops back to 500 fps.   
This phenomena happens with both Gnome and Xfce. (I don't use  KDE.)

Does anyone have an explanation for this phenomena?

BTW, on an old Thinkpad 600X running Fedora Core 3, etc., this phenomena 
does not occur.   Moreover, the gears visually turn very fast even 
though the frame rate is about 100 fps.

Regards,

--jed diem