The Acer i5 laptop comes with two graphics paths :

  • The i5 associated (Intel) chipset, and

  • A ‘discrete’ nVidia GT 750M / 4Gb graphics card (which looks like the more interesting OpenCL device)

One issue, though, is that the Intel graphics chip is low-power, and I love the ~7hr battery life. Whereas running the NVidia card (according to people on the internet) reduces the laptop battery life to 1.5hr.

So, it’s important to be able to switch the NVidia card on only when necessary (which is what the ‘Optimus’ technology apparently does on Windows).

Steps taken

To get the device driver installed for the NVidia card, here are the basic steps (ignore the first two) :

  • Fiddle around with doing it the hard way (install from souce download)

  • Try something promising-looking kmod or akmod

  • Cave in and do it the best way : bumblebee-nvidia

Cutting a long story short, the hard way uncovered the fact that the new kernel driver needs signing to work with UEFI. But that’s tricky.

Disable Secure Boot (on Acer)

So I disabled Secure Boot (no matter, at least for now : I don’t feel too insecure, being on a laptop with few internet-facing services).

See : http://acer–


This is apparently due to this bug in Bumblebee (source).

To fix this (so that it survives reboot), edit /etc/selinux/config :


Doing the NVidia install the Bumblebee way


Before the process lsmod | tail gives :

dm_crypt               23177  1 
crct10dif_pclmul       14289  0 
i915                  796439  3 
crc32_pclmul           13113  0 
crc32c_intel           22079  0 
ghash_clmulni_intel    13216  0 
i2c_algo_bit           13257  1 i915
drm_kms_helper         50652  1 i915
drm                   283747  2 i915,drm_kms_helper
r8169                  71677  0 
mii                    13527  1 r8169
i2c_core               38656  6 drm,i915,i2c_i801,drm_kms_helper,i2c_algo_bit,videodev
wmi                    18804  1 acer_wmi
video                  19261  2 i915,acer_wmi

Then do the bumblebee install :

yum install -y libbsd-devel libbsd glibc-devel libX11-devel help2man autoconf git tar glib2 glib2-devel kernel-devel kernel-headers automake gcc gtk2-devel
yum install VirtualGL 

yum -y --nogpgcheck install
yum -y install bbswitch bumblebee

yum -y --nogpgcheck install
yum -y install bumblebee-nvidia

To force a recompilation on the next reboot :

touch /etc/sysconfig/nvidia/compile-nvidia-driver

Once it’s correctly installed, modinfo nvidia will produce something like (notice that the same instructions also work for Fedora 21…) :

filename:       /lib/modules/3.17.8-300.fc21.x86_64/kernel/drivers/video/nvidia.ko
alias:          char-major-195-*
version:        340.46
supported:      external
license:        NVIDIA
alias:          pci:v000010DEd00000E00sv*sd*bc04sc80i00*
alias:          pci:v000010DEd00000AA3sv*sd*bc0Bsc40i00*
alias:          pci:v000010DEd*sv*sd*bc03sc02i00*
alias:          pci:v000010DEd*sv*sd*bc03sc00i00*
depends:        drm
vermagic:       3.17.8-300.fc21.x86_64 SMP mod_unload 
parm:           NVreg_Mobile:int
parm:           NVreg_ResmanDebugLevel:int
parm:           NVreg_RmLogonRC:int
parm:           NVreg_ModifyDeviceFiles:int
parm:           NVreg_DeviceFileUID:int
parm:           NVreg_DeviceFileGID:int
parm:           NVreg_DeviceFileMode:int
parm:           NVreg_RemapLimit:int
parm:           NVreg_UpdateMemoryTypes:int
parm:           NVreg_InitializeSystemMemoryAllocations:int
parm:           NVreg_UsePageAttributeTable:int
parm:           NVreg_MapRegistersEarly:int
parm:           NVreg_RegisterForACPIEvents:int
parm:           NVreg_CheckPCIConfigSpace:int
parm:           NVreg_EnablePCIeGen3:int
parm:           NVreg_EnableMSI:int
parm:           NVreg_MemoryPoolSize:int
parm:           NVreg_RegistryDwords:charp
parm:           NVreg_RmMsg:charp
parm:           NVreg_AssignGpus:charp

But where is the driver ?

Importantly, on boot, Bumblebee doesn’t install the new driver immediately.

Here’s my (meagre) understanding of how it works :

When you require the NVidia Graphics card (specifically, when you run an optirun GRAPHICS-PROGRAM on the command line) the bumblebee system appears to load the nvidia driver into the kernel, and tell it that it’s in control of a small screen (which matches the dimensions of X application you’re running). By the magic of X, the graphics card is none-the-wiser, and bumblebee then ‘takes a picture’ of the application at 60fps, and slaps it on the actual screen (still run by the Intel graphics chip).

Can this run OpenCL graphics coprocessor jobs?

Yes : Definitely. It can also run CUDA stuff too, if you install the CUDA SDK (not necessary for plain OpenCL).


There’s a problem getting the Nvidia card to wake up after a suspend, apparently. See my update post to resolve it with a suspend-hook workaround.

Martin Andrews

{Finance, Software, AI} entrepreneur, living in Singapore with my family.

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