Raspbery PI4 4GB model no video output above 640mb in config.txt

1st Official Post

    hello all, just got my new 4gb Raspberry PI4 in to day. loaded it up with Libreelec 9.2.5 and all updates. i then started playing around with the config.txt file as i have a notes from setting up my Raspberry PI3. the issue is when i adjust the GPU ram past 640MB the video output cuts out after reboot, just a black screen the TV knows somethings there but its just a black screen. i will see the Raspberry PI splash then nothing. i can still ssh into the pi, configure and reboot as need. i did try and kill -9 the kodi.bin to see if it was just a crash at boot but no luck. not sure if its a bug or if anyone else has had the same issue. i did started at 512MB and walked it up by 128MB each time, 640MB works however, 768MB+ will produce the no video output issue.

    let me know if anyone else has this issue kind of curious on it.


    Raspberry PI4 4GB model

    CPU - Broadcom BCM2711B0 quad-core A72 (ARMv8-A) 64-bit @ 1.5GHz.

    GPU - Broadcom VideoCore VI

    • Official Post

    Setting the GPU memory to 320 MB is the option most used by RPI4 users.

    I see no reason why doubling that amount would still be beneficial.

    The official docs for a long time basically said "Don't go over 512MB; there be dragons and boot problems over yonder. Plus, there's little benefit."
    Not sure when it changed, but there is now a 1GB max memory recommendation for the RPi4.

    I played with a bunch of config options and I scrape metrics every 10 seconds so I can compare videos against various tweaking. It's pretty rare that the videos I throw at it are ever more than 100MB of used GPU memory.

    I've not found a reason for why going over 320MB would be beneficial, but as long as you are greater than 128MB you should be fine.

    Hope that helps.

    Edit: Hrmmm.... I just noticed that the official docs now recommend not going over 256 on the RPi4 because of how the RPi4 handles memory. Hrm. I might need to do some testing.
    Memory options in config.txt - Raspberry Pi Documentation

    stack

    yes that was very helpful... not sure if i will keep my RP4 on libreelec machine and kick it back to my RP3 as it did just fine and i could use the RP4 for new projects in the works. but the native x265 support is nice