Severe problems with radeonHD 3470 and dual head conf

[Peter Boy]

Hi,

I bought a new box with an ATI Radeon HD 3470 (it is one of the rare
graphic boards with 2 DVI and passive cooling).

Installing F12 it automatically configures xinerama mode (better
spanning) as desired. But:

  -  Using a VGA adapter and VGA connection the second screen uses 
     a thinner, hard to read font and just a few different colors 
     (e.g. light grey will become white).

  -  Using DVI connectors directly the second monitor does not 
     receive a signal at all, allthough xrandr reports both monitors
     connected and xorg.log reads the monitors specifications (and 
     does not report any error). 

If I switch the monitors, the same effect. So it is not caused by the
monitor itself or the cable.


Any advice how to resolve it greatly appreciated.


Thanks in advance

Peter