Created attachment 84847 [details]
messages | grep radeon

I have a hybrid muxless laptop with intel+radeon:
#lspci | grep VGA
00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor
Graphics Controller (rev 09)
01:00.0 VGA compatible controller: Advanced Micro Devices [AMD] nee ATI Cape
Verde [Radeon HD 7700M Series]

I use openSUSE 12.3 x86_64 with
kernel              3.11-rc7
Xorg-x11-server     1.14.2
Mesa                git20130827
libdrm2             git20130722
libdrm-radeon       git20130722
xf86-video-ati      git20130827

The laptop hangs on boot while being on the battery.
When I plug it to the charger and try to boot it boots fines.

The attached file is from messages: two hangs when I tried to boot on the
battery and successful boot with power supply.