The HP 355 G2 totally freezes after using it for some time (browsing web, playing music). The CPU/internal GPU is an A8-6410 and a dedicated R5 M240. When it freezes it doesn't react to keyboard anymore(ctrl+alt+f1 etc) and display is totally frozen(not even cursor is moving anymore). I also couldn't find anything about this issue in syslog/xorg log.
(also, when frozen sound is playing in a loop)
It just froze again, this time a little different. First screen froze and music continued playing, then screen turned black and music looped. I think i didn't have these issues before i installed fglrx and during using fglrx. It seems like these freezing issues started after i removed fglrx. (I used apt-get purge fglrx* and moved xorg.conf so there shouldn't be anything left behind.) I also had freezes very often when using experimental opensource drivers/mesa from oibaf ppa. (https://launchpad.net/~oibaf/+archive/ubuntu/graphics-drivers) But these are not installed now.