alt.hn

8/13/2026 at 10:01:04 PM

Chestnut – eGPU dock with open-source firmware

 https://hwbusters.com/news/comma-ai-egpu-dock-runs-open-source-firmware-249-bare-799-with-an-rx-9060/

by txrx0000

8/16/2026 at 3:00:46 PM

The direct eGPU link if you're curious https://comma.ai/shop/chestnut

by reustle

8/16/2026 at 5:08:06 PM

I'm surprised that it's pretty much the same as the adapters you can get on aliexpress. Not even a case to protect it from feet in the passenger footwell. Especially compared to the windshield-mount unit, which looks like a very slick product. I suppose they can always improve it if there is interest in this first version.

by Gracana

8/16/2026 at 11:54:48 PM

It’s an incredibly dumb implementation and it feels like yet another case of “AI startup gettin’ while the gettin’s good”. It’s the dotcom bubble all over again. Do anything with AI and people will buy what you’re selling.

The RX 9060 has a TDP of 160W, but that’s the high end of what you can continuously draw from the 12v DC plug in a car, so it looks like they cap it at 100W. It has to be on the floor or under the passenger seat because it has to plug into that 12v outlet that’s usually in the front.

Things will get caught by the fan blades, and passengers will inadvertently kick it. Hopefully suddenly losing connection to the GPU won’t cause the car to hit a pedestrian or anything like that.

by gymbeaux

8/18/2026 at 9:48:39 AM

You forgot to ask "does it work". If the answer is yes, then what is the complaint? They can let other people 3d print cases and make wiring harnesses.

by roosterIllusi0n

8/17/2026 at 12:35:10 AM

wouldn't you also need to worry about the voltage spikes when you're running on battery vs starting the car if you're running an ICE? and would you need to unplug it if you, say, need a jump? feels like you'd also need to install a whole UPS on the other side too if you care about the hardware longevity (not factoring in the sheer amount of dirt/leaves/etc that'll just get caught up in the card itself)

by paimapi

8/16/2026 at 6:50:06 PM

Very much my own opinion, but this continues comma’s extremely cavalier attitude towards safety. PCIe connectors and GPUs are not vibration rated. What happens when you hit a bad pothole?

by buildbot

8/17/2026 at 2:09:29 AM

Soft disengage -- if the GPU fails it continues to drive via on-device model, alerts the user, and then disengages.

More generally, Comma's safety is handled by a microcontroller. The microcontroller limits steering torque commanded to a safe range for level 2 driver assistance and acts as a watchdog for the rest of the stack. Failure of openpilot causes it to disengage and sound an audible alarm.

by adinisom

8/16/2026 at 7:00:54 PM

I had a similar thought, but I suppose they decided to prioritize price on the assumption that initial adopters are handy enough to fashion an enclosure if they’d like one. Not a terrible assumption.

by 14u2c

8/16/2026 at 8:54:45 PM

Yeah, of all the parts to leave a out, sorting out a little enclosure is certainly the easiest and most likely to require customization.

by Gracana

8/16/2026 at 2:13:01 PM

the picture of that GPU installed on the side of the firewall tunnel reminded myself and my husband of a gadget they would have shown off in the original Batman series.

"Golly gee whilikers Batman, what is this high tech contraption?"

"It's a car tracker my good lad, see how sleek and easy to hide it is?"

https://blog.comma.ai/img/chestnut/install_footwell.png

by serf

8/16/2026 at 11:29:15 AM

I find comma.ai’s work pretty fascinating compared to the bigger fish in the self-driving world. There’s something quite human about it versus the Waymo’s and Tesla’s of the world.

by socratics

8/16/2026 at 11:32:53 AM

If you liked that, you should look into tinygrad

by itomato

8/16/2026 at 6:10:40 PM

I’m impressed by tinygrad. Full-featured deep-learning framework with ZERO dependencies, fully hackable, and orders of magnitude fewer LoC than PyTorch.

Want to run Qwen3.8 27B? Download the quantized model from HF, git clone tinygrad, then run `DEV=METAL python3 -m tinygrad.llm --max_context 8192 -m <GGUF File>`. Read the code and experiment - takes 1 minute.

Compare that with PyTorch (great, but almost impossible to comprehend and modify, IMO) or Mojo/MAX (complex and not even fully open source, not to mention that the Modular folks aren’t particularly nice). Tinygrad is a breath of fresh air.

by gip

8/16/2026 at 8:00:18 PM

"Zero dependencies" except Python, which is a pretty huge dependency.

by LoganDark

8/16/2026 at 12:30:16 PM

If you're like me and also wondered "huh, what's tinygrad up to?" apparently they now let you place $100,000 USD pre-orders on a $10M shipping container full of GPUs which they say will ship (literally it seems) in 2027.

by shrinks99

8/16/2026 at 12:40:06 PM

They're claiming a lot, but don't have much to show for it

by Numerlor

8/16/2026 at 2:55:01 PM

Did they have an actual metal container sitting outside their office building in San Diego? I would love to see it on the inside kinda like a walk-in tour you get from real estate listings

by jereees

8/16/2026 at 3:19:25 PM

he bought an empty container and he's looking for someone to build it out.

i ran 7MW and 20,000 gpus in containers in WA for mining eth for many years. it is a bad idea that he's trying to do. but george is george and the hype is real...

by latchkey

8/16/2026 at 4:30:18 PM

Do you have a write-up of this? I enjoy seeing these Playstation/ASIC/GPU mining installations which are usually some combination of incredibly clever engineering and duct tape.

by 3eb7988a1663

8/16/2026 at 6:10:33 PM

i ran 20k of those bc-250's too... but those were in a real dc. nice to see them getting use again.

sorry, no writeup other than what i've posted already.

by latchkey

8/19/2026 at 12:28:13 AM

actually they arent claiming much. and they already are doing better than 99% of other companies by having a buy button on their product page.

by eikonoklastess

8/17/2026 at 9:52:56 AM

Are they planning to do something like runware with their containers? ( Sonic inference pod)

by Bombthecat

8/16/2026 at 2:18:15 PM

I had my C3X audio device fail a month or so past warranty. It literally couldn't detect the sound card anymore. My car is not supported, and I've been on a fork since the beginning. Few line of code changes to get it working again and it's almost two years in use. And yes, I tried flashing any and all available releases/forks. The sound hardware was not visible in the kernel on all.

I've given up on the latest models and don't bother with the automatic cruise control. But just the lane centering is extremely helpful.

When people ask me about the device, I tell then it's the next version of power steering. And if one has never driven a car without power steering, one may not understand how much easier it makes the drive.

Thought about upgrading to the C4 as the original owner I could trade mine in for a discount. But the first thing I noticed on reddit threads were the C4 H/W failures, and that made me not want to bother figuring out what's needed to get the C4 running on my car. Wish they figured out how to bulletproof the device, would love to add the GPU.

by alex0com

8/16/2026 at 4:07:37 PM

This article triggered my AI sensitivity. Had to skip the second half.

by snovv_crash

8/16/2026 at 1:11:37 PM

Good, something that is needed for running LLMs and other non-LLM based deep learning work that doesn't suck or has poor drivers / firmware for.

I can rest assured that when I use this on any machine running Mac, Windows or Linux, I know it just works well with tinygrad.

by rvz

8/16/2026 at 6:31:32 PM

What I tried was based on theory (I haven't seen real device), bought Oculink dock, connected Oculink to M.2 connector, USB4 M.2 SSD Enclosure to connect to thunderbolt, whole thing costed 150euros :)

by ijsmtmmwiu

8/16/2026 at 2:41:32 PM

This bridge - does it actually support host PCIe->thunderbolt->PCIe device - my reading of it is that it's just handling USB commands that the bridge is turning into separate PCIe commands to the GPU?

by trebligdivad

8/17/2026 at 4:13:25 AM

My understanding is both USB 4 and TB use PCIe tunneling. Surely at this price point we’re looking at a USB 4 device. Thunderbolt has historically cost more due to licensing, which is now free I believe, but there’s still specialized hardware and requirements manufacturers need to adhere to.

by gymbeaux

8/16/2026 at 1:15:06 PM

I wonder if it's possible to do link aggregation for x8 lanes to GPU. I have two thunderbolt connections available, each x4. x8 has minimal losses for gaming.

by 47635274172635

8/16/2026 at 11:52:22 AM

Huh intersting that that they don't support any of the european Stellantis brands at all, wonder what they do differently that makes them incompatible.

by haunter

8/17/2026 at 11:09:23 AM

I’m working on integrating with a Jeep Renegade which was designed on the Fiat small-wide platform, and the CAN bus architecture is a non-starter for mainline OpenPilot support. OpenPilot requires every signal needed from/to the car is accessible by tapping at most two CAN buses, both of which must be accessible on the cable to the lane assist camera behind the rear view mirror.

On the Renegade, the adaptive cruise control activation and control signals are on a separate bus from the steering control signals, and the ACC signals don’t get up to the lane assist camera at all. OpenPilot support on this vehicle will require tapping CAN buses in two spots on the vehicle, and this is not a Comma-supported configuration. They want to be able to make a single interposer cable that plugs in between the lane assist camera and your car, and if that’s not possible they will never support your vehicle.

To attempt to support my car I am working on a gateway device that will bridge information from the powertrain bus to the fusion bus so it will be available at the camera (which is on the fusion bus and the chassis bus). But this implementation, which may not actually work but even if it does, will never be accepted upstream. And safety-wise, that’s probably the right choice for the project.

The sad part is I think the only signal that I need that I don’t have at the camera right now to make a safe implementation is ACC engagement. I’ve scrutinized every bit of every message on the chassis and fusion buses available at the camera and there is simply no signal that indicates if ACC is engaged.

One bit is all I need to get lateral control working. Well, assuming that once I start injecting control signals there aren’t other issues, that is. And that is not probably a safe assumption.

by hoss1474489

8/17/2026 at 3:52:17 PM

Thanks for the insider knowledge, very interesting!

I really think to buy my next car which is supported by comma

by haunter

8/16/2026 at 2:14:58 PM

Probably because they use a bus that's harder to on-the-fly rewrite or because they sign commands.

comma openpilot do its thing by faking stock self driving unit talking to actuators over the in-vehicle network; a modern car is like a bunch of Pi on a LAN hosting microservices, but on a car specific network standard, usually the one called CAN bus, instead of the 802.3 we're familiar with. The manufacturer stock units is usually a camera unit integrated CPU sitting behind a hump behind the rearview mirror. comma devices tap into the cable going in there, sending out fake commands to other computers handling cruise control, brake, steering, blinker... etc.

This can break two ways: some communication standards like FlexRay are harder to tamper and fake, or some newer cars have tightened security clearly in response to comma doing its thing too well, many following the new EU cybersecurity standards which require commands to be signed and/or each of those Pi-like modules to be crypto paired against each others.

I think Stellantis car always had the first of those two issues of having something difficult that are not strictly anti-hacker hostile architecture. But could be both or I could be wrong altogether. The comma devteam seem to like 2015-2019ish hybrids from such brands as Honda, Subaru, Hyundai and Toyota for the presence of the remote control features in the actuator modules && lack of security getting in the way.

by numpad0

8/16/2026 at 12:27:22 PM

From what I understood, when I looked into it a while ago, some car makers use an encrypted ODB2 (needed by Comma.ai to communicate driving instructions).

See for example: https://autel.us/security-gateways/, 'Automakers with security gateways installed include Stellantis (Dodge, Chrysler, Ram, Alfa Romeo, FIAT, and Maserati), Nissan and Infinity, Mercedes-Benz, and Volkswagen and Audi.'

by Gys

8/16/2026 at 4:27:49 PM

None of those busses are encrypted (at least not the majority I am familiar with). The security gateway is just a firewall.

by SV_BubbleTime

8/16/2026 at 8:30:06 PM

Toyota TSS3 is in fact encrypted; openpilot users who have TSS3 have to manually extract decryption keys from their cars to be able to talk on the CAN bus.

by LorenDB

8/16/2026 at 11:44:14 PM

How abhorrent and disgusting of Toyota! >:^(

by rustcleaner

8/16/2026 at 12:53:01 PM

They boast a "one year hardware warranty" (EU mandatory minimum is two) so I don't think they're targeting the European market directly right now.

by hnbad

8/16/2026 at 1:14:11 PM

They support Skoda which is not availabe in the US. Otoh VAG brand so it shares the same platform as Volkswagen which is available there

by haunter

8/16/2026 at 11:56:21 PM

Didn't George quit comma.ai?

by brcmthrowaway

8/16/2026 at 1:18:46 PM

Two things: 1. they have a cheap fuse (cents on the dollar) that’s not automotive-grade so your windshield mounted device fails in hot weather and doesn’t last past the hardware warranty. Known issue, doubt they ever fixed it.

2. 1B parameter model to stay between two lines. Why. Waste of time. Their product hasn’t actually changed in several years because they will never advance past lane keeping SAE Level 2.

I suspect for what they’re selling for $1,000+ these days, could you find a way to do for half? Less than that?

I mean after all, it still runs off a Snapdragon 845.

Nice tech, disappointing limitations and too expensive. The world moved on, Tesla is bad but a Waymo competitor would be more serious than this.

by bellowsgulch

8/16/2026 at 5:50:46 PM

You're not paying $1,000 for a cut down Android when you buy a Comma Four.

What you're buying is an entry ticket to Comma-land — where dozens of car models are supported, pre-made harnesses are just a buy button away, and everything is open source.

If George had chosen to go the closed source route, you might be paying $200 for a locked-down device and $200 every month for a mandatory subscription.

Which one makes you feel better? Comma as a business needs to be able to pay their employees.

by dermacentor

8/17/2026 at 8:28:10 PM

I want them to improve the product meaningfully beyond lane keeping, which besides lane changing (partially), it's the only thing it's capable of because they willingly choose not to extend the system to use more visibility.

by bellowsgulch

8/16/2026 at 8:27:27 PM

Comma-land?

Comma on, man.

by hypfer

8/16/2026 at 2:08:23 PM

> 2. 1B parameter model to stay between two lines. Why. Waste of time. Their product hasn’t actually changed in several years because they will never advance past lane keeping SAE Level 2.

Maybe... you're answering your own question there?

> I suspect for what they’re selling for $1,000+ these days, could you find a way to do for half? Less than that?

Genuine question: does anyone else anywhere sell something like this? An all-in-one retrofitable level 2 self-driving gadget?

by mft_

8/16/2026 at 3:03:42 PM

There are clone devices but nothing else I’m aware of

by Yossarrian22

8/16/2026 at 2:25:16 PM

[dead]

by Spikeysash

8/19/2026 at 1:03:02 AM

comma 4 was built from the ground up to avoid this problem. also they are building it in the us for about 500$ the 1000$ price tag isnt super unreasonable.

by eikonoklastess

8/14/2026 at 4:29:32 AM

[flagged]

by ncr100