ijustpostwhenimhi
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The official HATs aren't out yet, but there are plenty on AliExpress.
I went ahead and ordered one to try out.
It does "work" but I do get a lot of /corrected/ bus errors in logs.
I know high speed busses need very specific pcb design, so hopefully the official HAT will solve the errors. They're corrected errors, so the device still works, but the log spam is real lol
Speed test below. Note, the PCIe bus on the pi5 is x1 gen3, so max 1GB/s theoretical
smadge1
ChaiTeaGlow
Sweet :) I preordered a pi5 and I think it's coming early February. I will definitely wait for the official hat then.
lightfoot2
How does it compare to a 1-2tb little card (sdhc?)
schmooster
I think for speed, as @OP says, the pcie lane for the M.2 maxes out at 1GB/s, and some SD cards (e.g. SDHC v2) will max out at about 25MB/s
ijustpostwhenimhi
The sdcard I use is a Samsung Pro Endurance, I get 90MB/s read 70MB/s write. As for desktop responsiveness, I haven't tried booting off nvme yet. USB SSDs I've tried get 400MB/s read, 300MB/s write
schmooster
SDXC v5 is that sd card?
ijustpostwhenimhi
Not sure. The datasheet for the SD card states UHS-I (SDR104). Which is the same interface on the pi5 (SDR104). iirc the pi4 was DDR50
PepperoniAndFingernailPizza
I wonder if the bus errors are due to interference?
aducksayswhat
Apparently bus speed from what I've read, drop it down to gen2 helps, and a lot of uses won't notice the difference
ijustpostwhenimhi
It was! I added my own shielding to the ribbon cable and the errors went away /gallery/z98kpb5
ijustpostwhenimhi
Possibly. The ribbon cable is not shielded. The traces on the hat look autorouted. I remember something about PCIe needing matched impedance
PepperoniAndFingernailPizza
That could be it or possibly one of the components on the board. Jeff Geerling, where are you?! We need your help!
ijustpostwhenimhi
https://vilros.com/collections/raspberry-pi-5/products/raspberry-pi-m-2-hat-for-raspberry-pi-5 soon maybe? They're lots of other 3rd-pty I could try to, but I'll probably just wait for something official
PepperoniAndFingernailPizza
You're not Jeff Geerling are you? Just want to make sure 😂
ijustpostwhenimhi
Nope ;)