I’m using a custom flex pcb bc but I will probably switch over to a ribbon cable (similar to what they use on commercial pcie risers) as the flex pcb’s pads are very easy to tear off. The pcie slit would ideally be powered by the laptop as it is already getting cramped in the expansion bay cutout. It would be very difficult to fit another connector in there and I would prefer people not having to modify their expansion bay to use this board (when I get it working 
)
Sorry if I created more confusion with what I posted previously. I wasn’t meaning to have anything additional installed inside the expansion bay. I meant is it still possible to utilize a normal psu for the gpu outside of the expansion bay and the pcie slot be for connection/signal purposes only. Similar to how I currently run my deg1. And correct me if I am wrong, I believe you said you wanted to use a 40series for your set up? How do you think 75w will hold up on internal power when recommendation psu for 4070 is >200w ?
I believe you should be able to, however im not sure how voltage matching will work or if they will be an issue (because you will have the 12v from the slot and the 12v from the PSU connected to the GPU) need to look into that. Also for clarification, that 75W from the PCIE slot is so you can run other external PCIE devices without having to carry around another PSU , if you plan to use a GPU, you will need an external PSU
I don’t think that would be a problem, I have never seen a pcie device mix pcie slot power and external power appart from some nvidia gpus but they had dedicated electornics to make that work. Pretty sure doing that without active muxing would violate pcie spcs pretty hard anyway.
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great, thanks for the information!
@Pierre_Cruse Have you considered using MCIO connectors and not a real slot? Not sure if this fits your use case, but if so you could then use something like this to connect to actual card. Would give more flexible power options too.
Wow i did not know these existed, but i dont think it is a good solution because the whole reason i need the flex board is because the PCB that the x16edge slot is connected to needs to be raised above the interposer board for the PCIE connector to fit. I am trying to fit everything into the expansion bay so all you have to do to use it is get an x16 riser. I might consider using an x8 slot to save some space and perhaps add a connector to charge the laptop using the PSU powering the eGPU but i am getting carried away. Still need to get the basic functionality working.
I tested the board and the GPU turns on with its fans but there is no detection on the laptop. It also states that there is no expansion module detected.
Does anyone know if there are certain pins i need to pull up/down to enable the pcie lanes? The documentation on Framework’s Github is still very light.
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Here are some images of the first test
Did not work on first try but what does?
I do not know if i am missing a connection to allow laptop to try to enable the PCIE lanes/communication and for it to detect that an expansion bay is connected.
Here is a link to a video of the Test as I cannot post them here
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Have you added an eeprom chip to your board that indicates to the laptop’s EC that this is an 7700S graphics module?
There is an “expansion bay configuration” repo on Framework’s GitHub which can generate the contents of the eeprom for you, but you need to add the chip to the board for EC to read it and enable the pcie lanes and functionality from the CPU as far as I understand. Other projects for exoansion bay do that too.
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ahh, never thought of that. Ok ill look into that!
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Sorry, above my head with what you said here, but am I reading this as you are essentially tricking the laptop into thinking it is a 7700dgpu to get it to work?
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yep, because i think that is the only way to get the PCIE lanes enabled. I found the EEPROM chip and test pads on the 7700s module i disassembled and i ordered a TL866-3G programmer so i can dump its contents and take a look at them. This project was way more complicated than i expected
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The complicated part I fully believe. I love computers, but kudos to you guys that can go to this level of stuff. Ultimately what I think you are experiencing (though in different variations across projects) is what most others did trying to get an 8i board to work. Became a lot of hard work and costly. If you get it to work that would be amazing, but depending on what it took, the actuality of producing it for most other users is slim to none based on what you had to do to get there.
Just give me enough time and i will get there. I tend to hyperfocus on challenging stuff like this
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Awesome project, good luck with it! Is the current iteration of the design open source? We might be able to spot any other potential causes of the issue, I’d be happy to take a look!
Also a minor suggestion/feature request on later iterations, which should be pretty simple to add, would be to add a USB 2 port (which uses some pins on the power half of the interposer). Optionally if you can figure out full USB C power delivery to allow charging, that would be very cool, but would be quite a bit more complexity.
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Amazing. Just to say that this is a dream come true. Just wanted to say it.
i was thinking of doing this however the pcie slot takes up most of the available space in the rear. It is opens source however i have not updated the repo on over 6 months. I will update it when i have the next revision done
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No update, Been buys with exams :/. Im on break next week so i should be able to make some progress
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All good, life comes first. Take care of yourself. We will be here when you get back.
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