Changing CM4s in a Yellow

Hardware
1

Has anyone changed CM4s on a yellow as yet?

Currently have a PoE Yellow with a 1Gb Lite / no Wi-Fi CM4 (can run ESPHome but can’t compile new code). Have finally acquired a 4Gb version but with storage and Wi-Fi but would like to keep all storage on the MMC.

Is it just a direct swap or is any configuration needed before / after the change?

Thanks all,

S.

2

In the same boat, a Yellow PoE running on the only CM4 (1 GB RAM) I could get at the time, which barfs with ESPHome compilation.

Finally got a new one coming, would it be a straight swap or require a fresh install/restore?

Thanks!

3

Did you try the hook to make it run :point_down:

If you are using the onboard flash storage on the CM4 in some way it will be necessary to interact :hammer_and_wrench:

4

Limiting the compile threads didn’t make a difference to my 1Gb Lite without WiFi.

Straight swap for me, I think.

Caveat was that I run an SSD with everything on it (as stated, old CM4 had no storage). I switched CM4s and waited but nothing happened, but forgot I’d turned the activity LEDs off and my server picked it up as a new device and so I was aiming at the wrong address. When I thought it wasn’t working I put in the flash USB as if to set it up from scratch but, before it had a chance to run for more than a few seconds, realised my error and pulled the Ethernet (PoE). Restarted without the USB drive and all was well once at the correct address.

Note it totally screwed up my thread / HomeKit setup which took a bit to sort.

5

Hi,

did you get it run? I replaced the CM4 but it didn’t boot. Is there a fast way without the need of a complete reinstallation?

Regards,
Thomas

6

Same for me I only have a 2gb Version and want to upgrade now. Any ideas how to change the compute module? I have an ssd connected

I bought a new cm4 with wireless and 8gb of RAM because the 2 gb was not enough.

Followed the ideas in this one here:

Worked fine and everything is back as before.