Yes, true. Meaning dirty spi Yes and no. If SPI is detected and valid it is used. However if this one detects a microsd card with a boot loader it will chain-load this one to ultimately load the os from microsd. Having mixups between vendor and mainline u-boot and/or mixed blobs (like ddr training) this will much likely cause issues.

I will try to download and flash the armbian u-boot to SPI. The main issue is that I don't have a fixed USB-C 12V power supply In the meantime I instrumented the fusb302 driver in my Nixos U-boot (v2025.11) an I can see the negociation working and selecting 20v 3.25A with my Lenovo laptop charger. But Linux still stop sudently, but that's a nixos issue, not an armbian on I guess.

The solution I've found is to use a HDMI to VGA converter and use the VGA port

I already build a lot of images for another boards. My problem is uboot spl corrected 1536mb ram okay, but after that, it load uboot and say dram 2gb 0gb effective. Real ram is 1,5gb

@Sancho perfect. I will try it out and will inform you later. I have also discovered that the power adaptors packed with the iSG Box are low quality and some of those can't even reach 1,5 A. Which can cause instability issues and failed HA updates, install, armbian crashes, etc.