Updated my dual OcuLink 4i + DP board (and derived template), don’t expect many changes if the information we got doesn’t change besides the top edge connector offsets
The corner ended up fine, it’s not pretty and with good spacing like it was before, but I doubt it will create any significant signal integrity problems.
Order costs 34€ (49€ for the full size card) + shipping (~10€ for me) for 5 PCBs, and it scales really nicely (e.g. 63€ for 20 full size cards).
Nice work man. You did all great work!
Only becaus of interest: How would you attach it ?
Would you cut into the original-expansion bay and then print sth. with the 3d-printer? An do you have to solder the oxulink and dp-port by yourself or will this be soldered ?
I also wonder: Maybe i missed it, but could someone link the 8i version?
The latest files on Framework’s github shows a removable back panel. So we’d just need to 3d print one of those with port cut-outs. Or order from a 3d printing service, once someone uploads a design.
Ahh, i see. There is this little “door” (number 4 in the part-list) which you can remove. Then we can easily print this little part with the cut-outs for the oculink and dp ports.
Nice!
What if someone need this component one day. Are we allowed to use this for let it produce somewhere (for personal usage) or shall we contact you @seneral for the 4i or @Josh_Cook for the 8i?
Mine is open source and free to do yourself. Hence I focussed on a 4-layer design, 6-layer is even more expensive in small quantities.
Josh implied his 8i board is using 6 layers, which makes sense, only managed 4 layers because it’s a split design.
In general you very likely will be able to buy either version somehow, I assume Josh will sell his 8i version himself, as for the dual 4i, I invite others to do so (on your own risk after testing). I may do a small batch but I have no intentions of selling them unless nobody is filling that role to my satisfaction.
If you DO want to do yours yourself, join me in trying to bodge it:
The boards definitely need reflow soldering due to the OcuLink connectors, which has two rows of 0.5mm pitch legs, one of them hidden under the connector. So:
As you can see, pretty arduous. So again, as a normal person, I’d bet on somebody on your continent doing it larger batches (thus cheaper) and shipping it to you. Labour costs will be the biggest expense, e.g. if you do a batch of just 100 boards:
PCB <2€ no matter which version, Connectors ~9€, as low as 4€ for somebody well connected, 3D printed cover ?€, labour cost ??€
I noticed no license in your github. Even free use open source should have a license.
If you need a suggestion, perhaps GPLv3 or another which similarly prevents using DRM to disregard the intent of open source (Tivoization). Not that it’s really a risk here. It’s just good to use as standard. Practices like that are a nasty restriction of free use.
Great job guys, I’m looking forward on how these boards will perform - are they able to reach full PCI Gen.4 speed…
I was wondering whether ESD protection would be needed though. There are suitable parts from Littelfuse at least.
Youean if you have to be grounded? Yes, it’s your job to make sure you are grounded. Like when you diy a desktop PC. Then it’s also your job.
Should be no problem in my opinion. Just ground yourself to sth, before you start opening the laptop. The rest should be same as usual. Like when you put in a graphics card in a PCI-E slot. Also make sure dont touch electrical contacts.
Yes, I’m well aware of that. However might be worthwhile to build some extra safety there and enable potential hotplug. On theoretical level Linux has some support already, and with products like this it could become feasible to complete that implementation to something that actually works.
But PCI Express is not hotplug capable.
But more Important: The expansion bay itself is not hot-plug, if i remember correctly. You have to open up the laptop to take off (or swap) the expansion bay. So you would have to turn off the PC anyway.
And then it is like installing any other hardware. Don’t touch contacts and ground yourself before doing it.
I mean there is also no ESD Protection on ANY other hardware-device. Never heard of it. Or is there any device with that?
I think it’s unnecessary.
There is. Ports which are intended to be external have ESD protection built-in to their designs.
The issue is that ports which were intended to be used internal-only can lack the same level of protection. The ports, chips and supporting components just didn’t have the same need. Things like USB-C, HDMI, DisplayPort, Ethernet had to be designed from the ground up with ESD in mind. Think of how many people feel for a port with their fingertip to find the spot before plugging in.
Even if hotplugging never works, when it’s disconnected, you still have an external exposed connector that was not meant to be external. Think of people who use laptops in bed where blankets can brush against the laptop, and the ports. Laptops on cluttered desks with random food wrappers or whatever other objects.
I don’t know if ESD will be a serious problem for these Expansion bay modules, but it’s something that should be explored.
PCI Express is technically hot plug capable. It’s just typically only implemented on the enterprise level and rarely at that.
Hotplug is indeed part of the PCIe specification, and Linux kernel has some support for it. I’d assume something simpler like network controller would work already. Display drivers however I gather don’t have any support at the moment. Its however doable - its just software.
There is little article from one of the ESD chip makers:
The layout is simple, easily added to these existing designs.
Ah ok, yeah i meant internal Hardware. .
But i mean you have to open the Laptop to change it. Therefore it is in my opinion like internal hardware and therefore unnecessary.
I woulfd not say no to a hotswappable expansion bay and then i would also like sth like that. But because it is internal, i think it is unnecessary.
Its not internal since it has external Oculink connectors.
I think it would be just a matter of time when someone tries to plug in a cable with power on. Should be protection for that.
Ah, you mean the ports, i thought you mean the PCI-E side.
Ok, for the ports i dont know. Does all externlanports have ESD protection? Like Displayport, hdmi, usb and so on.
OcuLink is PCIe. It is just taking PCIe and exposing it externally. Nothing more.
Yes, they do.
We’ve created a form to be able to request samples of these: Expansion Bay Developer Program
We’re determining how to make these available in MP quantities as well.
Maybe a couple of pads can be added to the board so that optional esd protection can be soldered on?
for in line parts zero ohm resistors can stand in when no protection is implemented.
Now this, THIS is why I preordered a FRAMEWORK. 
I have been thinking of designing my own Oculink 8i expansion bay for the past month since I got my preorder in. @Josh_Cook I would love to purchase a fully populated board or just the bare pcb and hand solder (with needed reflow of some connectors) all of the needed components for your 8i/dp board when it is tested and fully working. If you do not want to sell anything I am OK with that, just wanted to put it out there. I was worried about having to do all of the dirty work that is learning how to design pcbs with high speed signaling in mind. I will be following this thread and anyone else that wants to accomplish this awesome feat very closely.