Comment 8 for bug 1401864

I rebooted the machine in the 7th comment and click fglrx via additional-drivers GUI. It could work.
/var/log/apt/term.log shows the installation completed normally.

-------------------

Log started: 2015-01-07 02:28:15
Selecting previously unselected package libck-connector0:amd64.
(Reading database ... 194354 files and directories currently installed.)
Preparing to unpack .../libck-connector0_0.4.5-3.1ubuntu2_amd64.deb ...
Unpacking libck-connector0:amd64 (0.4.5-3.1ubuntu2) ...
Selecting previously unselected package ncurses-term.
Preparing to unpack .../ncurses-term_5.9+20140118-1ubuntu1_all.deb ...
Unpacking ncurses-term (5.9+20140118-1ubuntu1) ...
Selecting previously unselected package openssh-sftp-server.
Preparing to unpack .../openssh-sftp-server_1%3a6.6p1-2ubuntu2_amd64.deb ...
Unpacking openssh-sftp-server (1:6.6p1-2ubuntu2) ...
Selecting previously unselected package openssh-server.
Preparing to unpack .../openssh-server_1%3a6.6p1-2ubuntu2_amd64.deb ...
Unpacking openssh-server (1:6.6p1-2ubuntu2) ...
Selecting previously unselected package python-urllib3.
Preparing to unpack .../python-urllib3_1.7.1-1build1_all.deb ...
Unpacking python-urllib3 (1.7.1-1build1) ...
Selecting previously unselected package python-requests.
Preparing to unpack .../python-requests_2.2.1-1ubuntu0.1_all.deb ...
Unpacking python-requests (2.2.1-1ubuntu0.1) ...
Selecting previously unselected package ssh-import-id.
Preparing to unpack .../ssh-import-id_3.21-0ubuntu1_all.deb ...
Unpacking ssh-import-id (3.21-0ubuntu1) ...
Processing triggers for man-db (2.6.7.1-1ubuntu1) ...
Processing triggers for ureadahead (0.100.0-16) ...
Processing triggers for ufw (0.34~rc-0ubuntu2) ...
Setting up libck-connector0:amd64 (0.4.5-3.1ubuntu2) ...
Setting up ncurses-term (5.9+20140118-1ubuntu1) ...
Setting up openssh-sftp-server (1:6.6p1-2ubuntu2) ...
Setting up openssh-server (1:6.6p1-2ubuntu2) ...
Creating SSH2 RSA key; this may take some time ...
Creating SSH2 DSA key; this may take some time ...
Creating SSH2 ECDSA key; this may take some time ...
Creating SSH2 ED25519 key; this may take some time ...
ssh start/running, process 10756
Setting up python-urllib3 (1.7.1-1build1) ...
Setting up python-requests (2.2.1-1ubuntu0.1) ...
Setting up ssh-import-id (3.21-0ubuntu1) ...
Processing triggers for libc-bin (2.19-0ubuntu6.4) ...
Processing triggers for ureadahead (0.100.0-16) ...
Processing triggers for ufw (0.34~rc-0ubuntu2) ...
Log ended: 2015-01-07 02:28:31