Did anyone think of a TPU expansion card? Google’s coral TPUs seem to be very efficient for developers working on Computer Vision. They are also very small and can fit into M.2 slots. What if we make an expansion card for something like the following?
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this module probably require very high speed interface. As listed on the spec sheet, it want PCIe gen 2 x1.
We can’t just grab PCIe from the expansion connector. Yes, we can use Thunderbolt bridge, but the cost for that alone would be about $100 (yep).
You could run it off USB, which will then be something like intel’s neuro compute stick.
Also, I think they might generate a generous amount of heat. Some cooling fins is probably needed.
I think currently this module fit onto the wireless card slot. which isnt bad because you can have a cheap usb wifi thingy for dirt cheap.
The better question, however, is whether you would actually need it, since you have a 15W CPU/GPU right there (with supposedly beefier AI core than last gen)
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I have to say I disagree with @Xavier_Jiang on the feasability of this idea. I actually think it should definitely be doable from a data transfer/energy standpoint.
Whilst the TPU benefits from a high speed interface, that is not really the limitation for expansion cards. Any expansion card should have a PCIe Gen 3 x4 available, which should be about 8 times the bandwidth required for that specific TPU card.
That is even enough to power an external GPU, which typically require monstrous amounts of bandwidth.
Power consumption is only up to 2 W, so I don’t suspect that to be a big problem, as normal expansion cards like HDMI and DisplayPort already seem to draw a constant 1W.
See: Linux battery life tuning
Whilst the Framework Laptop has a relatively powerful CPU/GPU combo, the big benefit here would be the performance/watt, which would be a lot more efficient than anything the Integrated GPU can do.
So for example a developer working on machine learning could benefit from these accelerator cards. Might be a great way to improve battery life.
I’m not sure whether the electronics will fit into an expansion card though…
In that case coming back to Xavier’s idea of simply moving the WiFi onto an expansion card and plugging the PCIe card into the slot for the WiFi module might just work.
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No. The expansion card communicate with the board with Thunderbolt, which does not support PCIe signals. You need a Thunderbolt to PCIe bridge.
In this case, we don’t need a additional expansion card because USB wifi dongles exist. Building a dedicated Framework usb wifi dongle is infeasible because demand is low.
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No. The expansion card communicate with the board with Thunderbolt, which does not support PCIe signals. You need a Thunderbolt to PCIe bridge.
Well, yes, it’s Thunderbolt (or rather USB4), but like you said, with a Thunderbolt->PCIe bridge, you can still get a PCIe connection. My point just was that bandwidth is plenty, as the port can provide the speed of a PCIe Gen 3 x4 connection.
There also seem to be versions of this card that connects directly via USB, so that would probably be even easier.
In this case, we don’t need a additional expansion card because USB wifi dongles exist. Building a dedicated Framework usb wifi dongle is infeasible because demand is low.
Yeah, demand for such a card is likely quite low. Just saying it would be possible.
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From the outside looking in, disregarding the difference in opinion about heat generation, you guys are basically saying the same thing.
I believe @Xavier_Jiang is just saying that it may be more cost effective to move the coral card into the WiFi’s internal m.2 slot so you don’t have to buy the bridge, and move the wifi out to USB.
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I’m actively working on exactly this.
Right now my current train of thought is to put the Dual TPU m.2 cord in an external enclosure, because I’m planning on replacing the existing network card with one that includes 5G that I’m going to try to harvest from an eBay parts laptop. I’ll have to put the new network card internally for antenna routing, so the TPU has to be an expansion card.
The current plan is waiting on framework releasing their reference oversize expansion card CAD file and using it to fit a USB4 to m.2 (e-key?) that’ll house the Dual TPU card.
I’m open to any alternative ideas.
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Is that possible? I know that WWAN cards require special motherboard resources (e.g., SIM card slot) and their connector is physically different (m.2 keyed rather than WLAN keyed)
Show me what you get. I want to see.
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The most cost-effective way to perform desired calculations is to simply run it on the CPU.
The most cost-effective way to perform desired calculations on said module is to put the module inside the machine’s WLAN slot and figure out some other methods for connectivity. Because as I said, Thunderbolt bridge is very expensive.
The most cost-effective way to perform desired calculations NOT on the CPU is to get something like Intel Compute Stick that interface over USB instead.
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Yes, the 5G laptops all use the same m.2 form factor and keying as normal network cards and ports like the ones in the Framework, and the nanosim slot is on the card. One with BT 5.2 and Wifi 6e would use the existing antennas plus one or two more for 5G (in my case, both mmWave and UWB), which will be tricky to manage, but doable, especially since I’ll soon have access to the proper equipment to test antenna placement and interference. It won’t be officially FCC approved, but it’ll be able to meet all the same requirements and specifications.
There will certainly be unknown unknowns and unforseeable bumps along the way, but I absolutely think it’s feasible.
Depend but Sierra Wireless have a eSim.
I’m sorry. But this sierra module is already absolutely massive and does not come with Wifi or bluetooth capability. I am not sure how you would fit those without the board getting uncomfortably large.
I mean they also have a USB version of the TPU… USB Accelerator and they sell just the chip which states under it’s tech specs:
PCIe Gen 2 or USB 2.0
Note: USB 3.0 is also available but requires special design considerations and support—for details, contact Coral Sales
I think someone with the willpower and knowledge could easily come up with an expansion card with this chip embedded.
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It is possible but the chip is ginormous, 1.5x1cm. That leaves half for USB-C circuitry and power supplies.
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Is it similar to the Intel Movidius Compute Stick?
I already made one. I haven’t tested it since the global shortage is so bad I can’t get a chip but we will see:
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