Problem after suspend / black screen (Intel Skylake)

Question

I have a brand new Dell Inspiron 15 (5559) laptop with an Intel Skylake i7-6500U CPU and an AMD Radeon R5 M335 graphics card.

Installation of freya 0.3.2 seems to have worked quickly and without problems. Overall, the system runs smoothly. But there are some errors when a desktop session is interrupted which might have to do with the drivers for the Intel graphics chipset in the current elementary kernel I'm running (3.19.0-56-generic).

One problem which I was able to (kind of) work around by installing kernel version 4.4 is described here: Dell Inspiron 15 5559 Problem at shutdown and logout (Intel Skylake)

But there is another problem: When the screen goes dark after x minutes of inactivity or when I suspend the session, upon return to activity the screen remains black. In the former case, the screen will just remain black. In the latter case, freya will first show the Pantheon greeter, and after you enter your password the screen will remain black. You can still hear sounds though (e.g. of a running video), so it does not look like the entire system froze.

Any hints? Thanks a lot because this is rather annoying. I cannot really leave my machine alone unless I want to force quit and reboot...

Answer 1

OK, so it looks like the problem is caused by missing drivers for the AMD Radeon R5 M335 graphics card. You can solve it by activating the proprietary drivers for AMD Radeon graphics card (called fglrx). You can choose between fglrx and the open source xorg drivers in the additional drivers tab of the update settings. After fglrx has been installed, the problem doesn't occur anymore.

So it looks like either the Xorg drivers - which are activated by default - do not work with an AMD Radeon M335, or the problem is the Intel Skylake graphics chipset because the AMD card isn't detected/activated at all without the fglrx drivers (this might be the case because when I ran "lspci -nnk | grep "VGA\|'Kern'\|3D\|Display" -A2" the AMD Radeon card wasn't detected at all, but I can't tell for sure).