My report, thank's a lot for the development :) Monitor ACER AL707, connected with dvi to vga adaptor $ # rhd_conntest 1:0:0 Checking connectors on 0x7280, 0x174B, 0xE190 (@01:00:00): Load Detection: RHD_OUTPUT_DACA HotPlug: RHD_HPD_1 DDC: RHD_DDC_0 RHD_DDC_3 /var/log/Xorg.0.log ... (II) RADEONHD(0): The detected amount of videoram exceeds the PCI BAR aperture. (II) RADEONHD(0): Using only 262144kB of the total 524288kB. (--) RADEONHD(0): VideoRAM: 262144 kByte ... (WW) RADEONHD(0): rhdAtomBIOSAllocateFbScratch: FW FB scratch area 536850432 (size: 20480) extends beyond available framebuffer size 268435456 ... (EE) RADEONHD(0): RHDLVTMAInit: unhandled connector type: 2 (II) RADEONHD(0): I2C device "RHD I2C line 0:ddc2" registered at address 0xA0. (II) RADEONHD(0): I2C device "RHD I2C line 0:ddc2" removed. (II) RADEONHD(0): Monitor "Acer AL707" connected to "DVI-I 2" ... (EE) AIGLX: Screen 0 is not DRI capable ...