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Big GPU, big models. Meet chestnut ⟶
chestnut<br>$799
ready to drive tiny chestnut eGPU dock
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Shipping Free US shipping, $30 flat rate internationally.
Using chestnut with openpilot? Choose ready to drive for everything you need to add desktop-class<br>GPU compute to your comma four.
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We think you’ll love chestnut, but if you’re not satisfied, send<br>it back within 30 days for a full refund.
1-year hardware warranty
1-year limited warranty against hardware defects.
Meet chestnut<br>chestnut is a compute upgrade for<br>comma four, built for<br>bigger models. It connects a desktop GPU directly to your comma four,<br>giving openpilot the compute to run its biggest driving models. The<br>first chestnut-class model has 30x more parameters and uses 100x more<br>FLOPs than the latest on-device model.<br>The ready to drive kit is the easiest way to bring that compute into your car.<br>tiny chestnut and ready to drive use the same USB-to-PCIe board and run<br>the same open-source custom firmware.<br>Read the launch blog post.
Using chestnut<br>With a PC<br>USB4<br>Connect chestnut to your computer and use it like any other USB4<br>dock.
USB3 or USB2<br>Use tinygrad<br>to access the GPU over a USB3 or USB2 connection.
Mac<br>Follow the TinyGPU setup guide<br>to use a supported GPU on macOS.
Join the #gpu-on-usb channel on the tinygrad Discord.
With openpilot<br>Pair chestnut with comma four<br>to run openpilot’s biggest models. The ready to drive kit<br>includes everything you need for an in-car setup: a GPU, a longer<br>USB cable, a car power cable, and mounting strips.<br>Join the #hw-chestnut channel on Discord.
In the Box<br>tiny chestnut<br>$249 chestnut
1m USB4
standoffs + thumb nuts
ATX power adapter
GPU power cable
ready to drive<br>$799 chestnut
1m USB4
standoffs + thumb nuts
ATX power adapter
GPU power cable
AMD Radeon RX 9060 8GB
3m USB3
car power cable
mounting strips
Setup Guide<br>Step 1 of 7<br>Install the standoffs<br>Thread the two standoffs into chestnut’s base so they are ready<br>to support and secure the GPU.
Step 2 of 7<br>Connect power to chestnut<br>Plug the GPU power cable into chestnut before installing the GPU.
Step 3 of 7<br>Seat the GPU<br>Align the GPU with chestnut’s PCIe slot and press it firmly<br>into place.
Step 4 of 7<br>Secure the GPU<br>Align the GPU with the standoffs and secure it with the thumb<br>nuts.
Step 5 of 7<br>Connect GPU power<br>Plug the other end of the 8-pin power cable into the GPU.
Step 6 of 7<br>Mount in your car
Mount in the footwell Or install under the passenger seat<br>Secure the assembled chestnut and GPU in the passenger footwell<br>with the included mounting strips, leaving room for airflow. If<br>there’s enough room, you can also install chestnut under the<br>passenger seat.
Step 7 of 7<br>Plug it in<br>Connect vehicle power Connect comma four<br>Connect chestnut to vehicle power and plug the USB cable into<br>your comma four.