ATI video card running slower after 7.3.1611

[taylormark]

Hi
We are using Dell 1950 computers which has the integrated ATI ES1000 chipset. The desktop graphics performance was fine with 7.3 Live CD build 1611, but starting with the Live CD 1708 and continuing to 7.5.1804 the performance is bordering on unusable. I can grab an xterm window and drag it around the screen and it keeps moving once I release it. During this time the xterm window is running at 100% cpu. I know this is an old slow chip but we looking at basic desktop functions only.
I have tried modifying
/etc/X11/xorg.conf.d/20-radeon.conf
and adding
Section "Device"
Identifier "Radeon"
Driver "radeon"
Option "AccelMethod" "exa"
Option "MigrationHeuristic" "greedy"
#Option "EXAPixmaps" "off"
EndSection

This did not change anything.

Does anyone have any suggestions ?
thanks

[TrevorH]

Read /var/log/Xorg.0.log and make sure it's using the driver you think it is.

[taylormark]

Hi
Thanks for the response !
I am pretty sure its loading the opensource radeon.
If I run lsmod on each version I get several lines showing "radeon"

/var/log/Xorg.0.log shows lots of lines with

(II) RADEON(0): Modeline " "

also have line
(II) RADEON(0): Acceleration enabled on each build

thanks