драйверы opengl не работают, glxgears не запускаются

Когда я пытаюсь запустить glxgears или ssh на машине и использовать OpenGL с флагом -X, я получаю следующее сообщение об ошибке:

Xlib:  extension "GLX" missing on display ":0".
Error: couldn't get an RGB, Double-buffered visual

Вывод lspci:

00:00.0 Host bridge: Intel Corporation 2nd Generation Core Processor Family DRAM Controller (rev 09)
00:01.0 PCI bridge: Intel Corporation Xeon E3-1200/2nd Generation Core Processor Family PCI Express Root Port (rev 09)
00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)
00:16.0 Communication controller: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 (rev 04)
00:1b.0 Audio device: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller (rev 04)
00:1c.0 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 1 (rev b4)
00:1c.2 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 3 (rev b4)
00:1c.3 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 4 (rev b4)
00:1c.5 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 6 (rev b4)
00:1d.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 (rev 04)
00:1f.0 ISA bridge: Intel Corporation HM67 Express Chipset Family LPC Controller (rev 04)
00:1f.2 SATA controller: Intel Corporation 6 Series/C200 Series Chipset Family 6 port SATA AHCI Controller (rev 04)
00:1f.3 SMBus: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller (rev 04)
01:00.0 VGA compatible controller: NVIDIA Corporation GF119 [GeForce GT 520M] (rev a1)
07:00.0 Ethernet controller: Atheros Communications Inc. AR8151 v2.0 Gigabit Ethernet (rev c0)
08:00.0 Network controller: Intel Corporation Centrino Advanced-N 6230 (rev 34)
09:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5116 PCI Express Card Reader (rev 01)
09:00.1 SD Host controller: Realtek Semiconductor Co., Ltd. RTS5116 PCI Express Card Reader (rev 01)
0f:00.0 USB controller: Texas Instruments Device 8241 (rev 02)

Это свежая установка Ubuntu, и странным образом проприетарный драйвер NVIDIA не указан в списке «Дополнительные драйверы». Настройки сервера NVIDIA X сообщают мне

You do not appear to be using the NVIDIA X driver.  Please edit your X configuration file (just run `nvidia-xconfig` as root), and restart the X server.

Если я это сделаю, мне будет предложен экран 640x480 в дополнение к вышеуказанным проблемам (я исправил эту конкретную проблему с помощью mv /etc/X11/xorg.config .backup /etc/X11/xorg.config)

Результат вывода ldd $ (который glxgears) равен

linux-vdso.so.1 =>  (0x00007fffc0bff000)
libGL.so.1 => /usr/lib/nvidia-current/libGL.so.1 (0x00007f6e0f10d000)
libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f6e0ee13000)
libX11.so.6 => /usr/lib/x86_64-linux-gnu/libX11.so.6 (0x00007f6e0eade000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f6e0e721000)
libnvidia-tls.so.302.17 => /usr/lib/nvidia-current/tls/libnvidia-tls.so.302.17 (0x00007f6e0e51e000)
libnvidia-glcore.so.302.17 => /usr/lib/nvidia-current/libnvidia-glcore.so.302.17 (0x00007f6e0c16c000)
libXext.so.6 => /usr/lib/x86_64-linux-gnu/libXext.so.6 (0x00007f6e0bf5b000)
libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f6e0bd57000)
libxcb.so.1 => /usr/lib/x86_64-linux-gnu/libxcb.so.1 (0x00007f6e0bb38000)
/lib64/ld-linux-x86-64.so.2 (0x00007f6e0f448000)
libXau.so.6 => /usr/lib/x86_64-linux-gnu/libXau.so.6 (0x00007f6e0b935000)
libXdmcp.so.6 => /usr/lib/x86_64-linux-gnu/libXdmcp.so.6 (0x00007f6e0b72f000)