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rane29
Currently I'm running Mandy 9.2 with a Radeon at 1600x1200 rez. Everything is fine accept for one thing, there seems to be static on the screen whenever a window moves (or even now as I type this). While hard to describe, it's as though the image is being echoed on another part of the screen.The refresh rates were automatically detected, and 'lsmod | egrep rad' shows the radeon driver loaded.

I should point out the video is perfect at all resolutions in Windows, and 800x600 works fine in Linux. Only these higher resolutions cause the static problem. The monitor is an Envision en-910e, but during installation I had selected "Generic" as the drivers weren't listed.

Any help would be appreciated.
hughesjr
I think you best bet is to manually edit the /etc/X11/XF86Config file and add your vertical and horizontal scan rates ... which will allow Linux to hopefully pick a better frequency at the higher resolutions.

You are looking for the variables named HorizSync and VertRefresh. For my NEC Multisync E1100, the values are:

HorizSync 31.0 - 82.0
VertRefresh 55.0 - 120.0


I couldn't find a manual for that specific model at Envision Monitors; however,
I found info for the Horizontal frequency at Amazon.com:

HorizSync 30.0 - 95.0

I couldn't find info for vertical frequency for this model ... but all 17" and 19" CRTs listed at Envision Monitors had this for there Vertical Refresh:

VertRefresh 50.0 - 160.0

If you have a monitor manual to verify the info, I would do that ... then edit the file:

/etc/X11/XF86Config
(or /etc/X11/XF86Config-4 if it is there)

and update the monitor frequencies to:

HorizSync 30.0 - 95.0
VertRefresh 50.0 - 160.0

Then restat the PC and you should get a better picture...

Notice - Setting your frequencies to non supported values can fry your monitor .... please verify all settings and ensure they are correct via documntation or with the manufacturer. I have tried to find the proper settings and I think those are correct, but I'm not sure!
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