Three things from this week: ttftw 2023w08

Trying out something new, we’ll see if it sticks. I read a lot of random stuff online and rather than just forming an opinion and dropping it I thought I’d try sharing my thoughts. That’s all a blog is anyway, but sometimes they’re just little thoughts. Since each one is just little I’m putting a few together. I won’t claim they’re related in any way except that the all went through my brain.

Three things from this week.

This week I’ve been shopping computer parts and thinking about a cohesive plan for my next desktop. I also came across a unique GPS for the Raspberry Pi.

AMD X670 vs X670E chipset

The X670E offers more PCIe 5.0 lanes than the X670. Motherboard manufacturers have some discretion in how they expose the lanes. It’s hard to tell the difference between all these options and the marketing materials only make it more murky. The product names sometimes say X670E even though the specifications say X670. For example this Asus ROG Crosshair X670E Extreme has a lot of extremes in the name but the tech specs section it clearly says X670. The board has 2 PCIe x16 and 2 PCIe 5.0 M.2 sockets so I think that means it does indeed have the X670E indicated by the model name. Given the number of variables it’s important with this generation of boards to look at what you expect to be able to use and confirm it in the manual after narrowing down the choices. At least PC Part Picker is still out there helping to narrow down the list of options quickly.

T-Slot, V-Slot, Makerbeam

T-slot extruded aluminum beams come in a variety of sizes and shapes. I’ve seen lots of 3d printers, home CNCs and other equipment built with it. But I’ve never figured out how to get started building with it. So when I realized that people are building custom computer cases out of these parts I saw a solution to my own problem. I want to build a new computer in my current computer case and repurpose most of what’s in there as a lab machine. Maybe I’ll put some extra network cards or weird PCI devices in it.

Anyhow, I spent way too long looking at various profiles. Makerbeam is a branded version of extruded aluminum. The main makerbeam parts use a 10mm x 10mm T-slot profile. They also do Makerbeam XL and OpenBeam in 15mm square. They’re in Europe though and don’t have a lot of distribution where I am. I picked up a kit of the 10mm parts from Amazon but the longest pieces are 30cm. No good for my computer case but I’ll find other uses for it.

I really liked shopping around 8020.net. Their smallest metric profile is 20mm but it sounds like they have more accessories in the 25mm profile. Their gallery shows a lot of great projects - I’d love to see more complete kits available. Especially that backyard all-grain brewing build…

Nice GNSS for Raspberry Pi CM4

Timebeat is selling a nice GNSS module that fits in between a Raspberry Pi CM4 and the standard carrier board. The board has pads to populate one of two GNSS module form factors. With the MAX-M10S it’s really inexpensive ($57 at time of writing). The other two options use the LEA-M8S or LEA-M8F. That last option is the most interesting - the ublox page highlights PTP support. This high accuracy time synchronization is well-matched with the temperature compensated oscilator (TCXO) modules also offered from Timebeat. Of course the more expensive module pushes the prices up significantly as well.

The weird connector interface has pros and cons. It sits on top of the carrier board and under the CM4. I assume they need some signals from the board-to-board connector which aren’t available from the RPi 40-pin GPIO header. It’s nice that the GPIO header is free but it’s unfortunate that the Timebeat module won’t necessarily fit other carrier boards, such as the Piunora.

One thing I haven’t figured out yet is whether the Timebeat software is necessary for using the board, or if it integrates well with typical Linux PTP, Chrony, and GPSd.

So there we go.

Three things that I thought about for a while this week. All were on my mind and now we both have a spot to remember what those links were. Hope you get some use out of it too. Let’s see if I come back in a week or a month with three more.

• ttftw