So, I was wondering. The USB port on the 5070 supports charging. Could I use that to power the graphics card without needing an ATX power supply? I understand that the oculink adapter kit isn’t available currently, but I’m still wondering about if this would work, or what might happen if I tried.
How are you planning on plugging the occulink cable into a USB port?
I guess maybe I am not fully understanding your question? You’re asking about the 5070 (mobile) gpu specifically designed by framework for the 16? You shouldn’t need oculink for that. It connects directly into the back of the laptop using the 8 pcie lanes via the interposer (you usually have to make sure you order the interposer with the gpus aswell). You plug your 180/240w charger into your usbc on your laptop and it will power everything (though you’ll likely still get battery drain depending on how heavy your usage). The original 7700 did not support usbc charging in the back compared to what they claim on the 5070, so I would presume that means if you really wanted to, you could plug your charger into that port on the back instead of the side and it would do the same? Though I would think the concept is more for docks where it supports image and charge. Don’t quote me on that as I haven’t tinkered with that before.
I’m guessing he means plug the gpu into occulink, and use usb PD for the power instead of getting some jerry rigged ATX power supply. It’s an interesting idea. Unfortunately, I think the answer is no. The output power of those ports is limited to like 15W I believe.
If you had a second usb c power brick though, maybe?
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You are correct. They don’t support enough power out to power a GPU. The exact amount I don’t recall but I remember having a discussion with a Framework engineer years ago about it. External power for a GPU will be required unless it’s a GPU meant to plug into the FW16.
To those confused, I mean that the oculink adapter will allow the card to work as an eGPU. I’m asking if powering the card via an ATX power supply is required, or if I can simply use the built-in usb-c port to power the card, as the 5070 is able to receive power through the usb-c for charging.
i would say probably not? but i don’t know the max power output from the best FW16 usb port.
If the card really accept power that way, then it would probably be a power budget limit more then anything else.
but i find it strange that a graphics card could be powered from it’s usb-c plug, are you sure about this?
if you plug the card in a pcie slot, and no extra power cables, beside the usb-c to a powerfull USB-C charger, i don’t think it will boot.
i think the power OUTPUT on the 5070 is there in case you want to use a usb-C powered screen, that way you don’t need 2 cables.
I would say no because:
-The chip managing power and the voltage converters are on the mainboard.
-Oculink is a strictly data protocol, so the usual power connection is severed with the devkit.
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I’m kind of under the impression that it might not work because it might not be designed that way. Typically it would be installed in a FW16 and would get power via the interposer. The USB-C port on the 5070 allows 240W power for the laptop and I’d think that would passthrough to the mainboard before being distributed to the GPU and other components (I’m not an engineer so I can’t say for certain). I’d think the circuit board that would hold the GPU would probably need power that isn’t through the GPU, but if the FW16 can do it I don’t really see why the dock couldn’t also do it. It would certainly make for a cleaner look with just a USB cable plugged in.
I guess one way to potentially test the feasibility would be to disconnect the battery from the FW16 and with power plugged into the GPU see if it boots. That being said it doesn’t mean that the board for the eGPU setup supports USB PD. I’m inclined to think they didn’t design it with that in mind.