Bug#503664: xserver-xorg-core: Dual head with Radeon HD3200 - heads partly overlay each other
>> Anyway this version only has produced a black external monitor :)
> If you know for sure which resolution+refresh-rate should be used, you
> can use ModeLine+PreferredMode in the corresponding screen section. See
> section III.5 of http://wiki.debian.org/XStrikeForce/HowToRandR12
>> So definitely not a hw limit. Seems a radeon driver issue?
> Or maybe a Virtual size config limit? Can you try adding
> Virtual 3000 1600
> in the Device section to force the maximal size to be larger?
> Then try again with your 1440+1280 setup (with ModeLine+PreferredMode if
> needed) with Xserver 1.5 from experimental.