Board:lenovo/Nvidia Optimus

Nvidia Optimus

Nvidia Optimus is mainly an ACPI feature to control power of the dGPU.

Coreboot 4.6 doesn't support Nvidia Optimus.

Hybrid Graphics / Switchable Graphics

Hybrid graphics is a feature used by a notebook that has two GPUs and a MUX to switch the notebook's panel to one of the GPUs. Only one GPU is active at time, allowing to save power and making display handling on software side easy.

Coreboot does support hybrid graphics and you can select the GPU to use at boot (using a CMOS setting, through nvramtool or nvramcui). Supported Notebooks:

• Lenovo T400/T500
• Lenovo T420/T520
• Lenovo T430/T530

PowerXpress (Mobile)

PowerXpress automatically switches the graphics depending on AC/battery state and user preference. Coreboot 4.6 doesn't support PowerXpress.

Dual graphics

Dual graphics is a feature used by a notebook that has two GPUs and where the iGPU is connected to the panel and where the dGPU used to offload rendering to. It can be used on MUXed devices and MUXless devices.

Requirements:

• Active both GPUs at boot
• Include the VGA Option ROM for the dGPU
• Include the VGA Option ROM for the iGPU or use Native Graphics Init
• On Linux you can use DRI_PRIME=1 to offload 3D rendering to another GPU.

Supported Notebooks:

• Lenovo T400/T500
• Lenovo T420/T520/T420s (depends on: https://review.coreboot.org/#/q/project:coreboot+branch:master+topic:_ROM, https://review.coreboot.org/#/c/coreboot/+/22337/)
• Lenovo T430/T530/T430s (depends on: https://review.coreboot.org/#/q/project:coreboot+branch:master+topic:_ROM, https://review.coreboot.org/#/c/coreboot/+/22337/)

Proprietary Option Rom usage

Please note that you have to use the Nvidia/AMD Option Rom to drive the second GPU. For the Intel GPU you are free to use the Option Rom or use Native graphics Init.