Display Resets Every Sixty Seconds

Running both vim4-ubuntu-22.04-gnome-linux-5.4-fenix-1.0.11-220620-emmc-develop.raw.img.xz and vim4-ubuntu-20.04-server-linux-5.4-fenix-1.0.11-220620-emmc-develop.raw.img.xz I have experienced periodic, momentary screen blanking on my VIM4 with New M2X Extension board installed, that I believe to be display reset behavior. My display is a Lepow Type-c Portable Display. I’ve not experienced this issue with any other computer I’ve connected to it.

Am I the only one seeing this?


I ran into something similar, ended up being the power supply I was using to power the VIM4. Changed to something beefier and haven’t had an issue since!

Thank you for the information.

I am powering the VIM4 with a 60 Watt USB-C charger, that’s about double the 30 Watt power supply Khadas specifies for the VIM4. So, I don’t believe power starvation to be the cause of the display interruptions I am experiencing.

The issue was also evident before connecting the New M2X Extension board and SAMSUNG 980 1TB M.2 NVMe SSD.


It might very well be, if memory is correct the HDMI chip has a minimum V of 4.8. Not much wiggle room on that.

Even though the wattage might be correct, much of if depends on how well the Vreg is in the adapter. I had a flaky supply and it created many problems. Just cut the connector off the USB c cable and connected directly to a stiff Siglent lab supply. Finally found a medical grade wall plug-in that can handle the NVMe/SSD current and the VIM. So far so good with them. I do run mine at 6V not sure what Khadas recommends for optimum performance.

Also, if you have a cheap cable you will have problems. After cutting off the connectors on several cables I found the small diameter signal wires were also carrying the V+. Even with a stiff power supply the resistance of the small wire is high enough to create a pretty healthy voltage drop. V+ wire needs to be much larger diameter for the 5 amp rating.

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