What it changes
- It gives comma four a supported external-GPU path.
- It runs the released 880-million-parameter Chestnut model.
- It gives comma room to develop larger driving models.
Chestnutcomma GPU
What is the comma GPU?
It is a desktop graphics card that connects to comma four through Chestnut. It runs a much larger openpilot driving model.
Short answer
Chestnut is the connection. RX 9060 is the GPU.
comma four normally runs its driving model on a Snapdragon 845 MAX. Chestnut lets it send model work to an external AMD Radeon RX 9060 8GB. The card has faster dedicated memory and much more graphics compute, so it can run a model that is too large for the mobile processor.
RX 9060desktop GPU8GB, non-XT card
288 GB/sGPU bandwidthinside the graphics card
880Mreleased modelparameters in openpilot 0.11.2
Optionalnormal usecomma four works without it
What stays the same
Your car must already be supported. openpilot still controls only the functions that the car and software support. You must supervise every drive. A larger model does not make the system autonomous.
Why call it an eGPU?
eGPU means external graphics processing unit. The RX 9060 sits outside comma four. A USB cable and the Chestnut hardware connect it to the device. The 288 GB/s number is the speed of memory inside the card. It is not the USB cable speed, and it does not mean driving becomes 9.6 times better.
Read comma's announcementQuick answers
comma GPU questions
Does comma four have a GPU?
comma four has a mobile graphics processor in its Snapdragon 845 MAX. Chestnut adds a separate desktop Radeon RX 9060 for much larger driving models.
Does the comma GPU make the car self-driving?
No. openpilot remains supervised driver assistance. You must watch the road and be ready to take control.
Do I need Chestnut to use comma four?
No. Normal comma four works without Chestnut. The eGPU is an optional model upgrade.
Photos: comma.ai. CommaGuide is an independent guide and is not affiliated with comma.ai.
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