OK, it is working now. I previously forgot to manually install the gcc4.9 dependencies.
Just to summarize in case someone went through the same struggle: 1 - Installed Ubuntu 15.10 -> Instead of being prompted for my disk encryption password I get a black screen! The screen actually goes of! This is related to my "AMD Radeon HD 7850"... -> Luckily it is possible to enter the password in the "dark" - Workaround: add "GRUB_GFXPAYLOAD_LINUX=auto" to grub. 2 - Obviously, if you buy this graphic card you kind of plan to use it, so I installed fglrx (updates and no updates) -> system no longer boots, and it is not possible to enter the disk encryption at all. -> To address the disk encryption issue had to remove "splash" from grub configuration, leaving it like this: GRUB_CMDLINE_LINUX_DEFAULT="quiet", the previous (1) grub hack no longer works can be removed... -> the driver itself does no work, had to remove it after booting in single mode. 3. Installed the packages proposed on the previous post (updates) -> Together with the previous (2) grub hack everything is working again. I mean, not as good looking as it should but, it is working. This was the reason I left Fedora 4/5 years ago!!! -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to fglrx-installer in Ubuntu. https://bugs.launchpad.net/bugs/1493888 Title: FGLRX incompatible with gcc 5 Status in Release Notes for Ubuntu: Fix Released Status in fglrx-installer package in Ubuntu: Fix Released Status in fglrx-installer source package in Wily: In Progress Bug description: With a R9 280 and FGLRX on ubuntu 15.10 the graphics lock up. I am able to SSH into the machine. I booted the older kernel (4.1.0-3-generic) and it works with FGLRX. After purging FGLRX and using xserver-xorg-video-radeon I am able to get the graphics working, but even it has issues with my display port (The DVI ports are working correctly). ProblemType: Bug DistroRelease: Ubuntu 15.10 Package: fglrx (not installed) ProcVersionSignature: Ubuntu 4.2.0-7.7-generic 4.2.0 Uname: Linux 4.2.0-7-generic x86_64 ApportVersion: 2.18-0ubuntu9 Architecture: amd64 Date: Wed Sep 9 09:29:54 2015 EcryptfsInUse: Yes InstallationDate: Installed on 2011-01-07 (1705 days ago) InstallationMedia: Kubuntu 10.10 "Maverick Meerkat" - Release amd64 (20101007) ProcEnviron: LANGUAGE= TERM=xterm PATH=(custom, no user) LANG=en_US.UTF-8 SHELL=/bin/bash SourcePackage: fglrx-installer UpgradeStatus: Upgraded to wily on 2015-08-18 (21 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-release-notes/+bug/1493888/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp