Questions about mainboard and expansion module for astrophotography

[Kwangmin_Ryu]

so I was using raspberry pi before but recently, it was having hard time and keep shutting down. I was tired of dealing with it, compiling programs for it. so now I’m trying to move to x86 system and found framework mainboard can be used by it self which got my attention.

Before I proceed with it, I got few questions about it.

1. on website, it is saying that mainboard size is 295mm x 229mm which is almost same size as A4 paper size. But when I look on reviews and photos, it doesn’t seem like it is that big. What is accurate size of it?

2. I’m noticing that expansion is using usb c port. What usb version is it using on it? And is it possible to plug usb devices directly into port?

3. My devices are using usb a port, so I’m going to make a usb a hub for it. Questions is I need 4 port hub which is bigger than what it can fit into. so I’m curious if anyone attempted to use 2 expansion port for 1 expansion card.

4. How much power does it draw? Is it possible to do undervolting? For astrophotography, most of time we don’t have access to power so just need to rely on power bank it so power draw is one of important thing.

5. How does it perform with linux? I’m noting there is issue with newest kernel.

[Arya]

1. definitely a mistake, that’s about the laptop size. the mobo is 220 wide and about half as high? there’s DXFs here if you need more exact references.

2. It’s USB 2, 3 and 4 (?) support, with Thunderbolt, DP alt-modes and charging available on all ports. and yes, it works just the same if you plug things directly into the mobo!

3. bigger than what it can fit into? what do you mean?

using 2 expansion ports for 1 expansion card is semi-viable, but mostly for “bare mainboard” projects, not for in-laptop use - because of this:

tho, people have prototyped things for in-laptop use, but there aren’t any completed projects afaik.

4. not sure, maybe someone else has measured it. here’s a FAQ with some links that might contain useful information for gauging that. My guess is that putting the CPU into sleep when possible should give you plenty of runtime!

5. AFAIU pretty good, but I don’t use a Framework laptop, so, can’t say.

[vl_dang]

@Kwangmin_Ryu

• on website, it is saying that mainboard size is 295mm x 229mm which is almost same size as A4 paper size. But when I look on reviews and photos, it doesn’t seem like it is that big. What is accurate size of it?

Referencing this Mainboard/fw_main_pcb_generic_2_w_fan.pdf at main · FrameworkComputer/Mainboard · GitHub it should be around 233mm x 105mm

@Kwangmin_Ryu

• I’m noticing that expansion is using usb c port. What usb version is it using on it? And is it possible to plug usb devices directly into port?

It’s USB4 so yes you will be able to use any USB devices

@Kwangmin_Ryu

• How much power does it draw? Is it possible to do undervolting? For astrophotography, most of time we don’t have access to power so just need to rely on power bank it so power draw is one of important thing.

it’s about 10W at idle (nothing crazy). I’m a data guy so my baseline might a bit high for other people, using a lot of RAM and stuff.

@Kwangmin_Ryu

How does it perform with linux? I’m noting there is issue with newest kernel.

Kernel 6.0 work perfectly. Kernel 5.19.12 is the one with problem, but 5.19.13 fixed it

The problem I foresee with astrophotography is vibration. It has a fan and it will spin, especially the 12th gen. So I imagine you will have to find some way to isolate the mainboard from the sensor.

[Fraoch]

@Kwangmin_Ryu

And is it possible to plug usb devices directly into port?

Of course, but these ports are soldered directly to the mainboard. Limit the plug ins and removals, and be careful (perhaps not so easy in the dark!) If you break one of these you lose 1/4 of your I/O and would need a new mainboard.

That’s why the expansion cards exist, if they break they’re cheaply and easily replaced. In your case, better to plug in a USB hub and keep it plugged in and plug/unplug what you want from that. With 40Gbps available, there’s lots of capacity for anything.

[Kwangmin_Ryu]

Thank you for your answers.
For expansion card, I’m going to build custom case for it so there is no separation between 2 ports. And depending on much power output it can do, I might use one more port for just power so it can keep up to my power requirements. I’m not sure if it is possible to do that so I was wondering if anyone have done it before.