radeon: different colors on different heads?

[Csillag Kristof]

Hi all,

I have two identical (Samsung 214T) monitors attached to the two outputs
of a FireMV 2200 PCI card (RV280 based).

I see something strange: there are some colors (mostly from the dark
blue range) which are rendered completely differently by the two
monitors. (One of them does black instead of dark blue.)

Here is a test pattern I created:

http://picasaweb.google.com/lh/photo/z8cGJO-qRn7iwUY7NLB7Fw?authkey=Gv1sRgCM60oc7kuoW24gE&feat=directlink

..and how it looks like:

- on monitor 1 (buggy):

http://picasaweb.google.com/lh/photo/aK0472ZaVi6tQzgcYOBGyA?authkey=Gv1sRgCM60oc7kuoW24gE&feat=directlink

(The diagonal black strip is not the error in the photo; it's the error
I am complaining about.)

- on monitor 2 (normal):

http://picasaweb.google.com/lh/photo/gXvQ9y72WMDhrjq3kQzicw?authkey=Gv1sRgCM60oc7kuoW24gE&feat=directlink

    * * *

If I switch the connections of the two monitors, the problem jumps to
monitor 2, so it's not the monitor's fault; something must be wrong with
one of the heads of the video card.

   * * *

Can this be something the software driver (radeon) does, or is this
likely a hardware problem?

Thank you for your help:

    Kristof