Power consumption in idle about two times too high

[kuleszdl]

Hi,

my A64-OLinuXino draws around 0.39 Amps at 5V in idle with network connected. Another board with basically the same A64 chip and peripherals (the "old" Pine A64, not the LTS model) draws only 0.21 Amps. Both boards don't have eMMC or external peripherals connected.

Both systems are running the official Debian stable kernel (4.19). I use the dtb from kernel 5.4 on the A64-OLinuXino as otherwise ethernet is not working. The A64-OLinuXino runs u-boot v2020.07 and the Pine model v2020.01 or something like that.

Yet, the difference is quite striking and you can also feel it as the A64-OLinuXino gets quite warm while the Pine A64 stays cold.

Any ideas how how to fix that?

Edit: Cause could be faulty power cable, I will try again with new cable.

[LubOlimex]

It is a complex setup, it probably will not be an easy task to determine why one consumes more than the other. Different boards can draw different current, it is not just the A64 chip there but power management units, regulators, transistors, battery chargers, etc, etc a lot of hardware differences. More expensive parts would have less losses. Furthermore, some of the settings of the PMU can be controlled and set by software means.

[kuleszdl]

Well I rather expect something "stupid" such as the HDMI output or the GPU being powered on while not being needed. But I will wait for my new cable to arrive to rule out this source of error first.

Has anyone else done similar measurements and can confirm or reject my findings about the device drawing ~0.4A in idle with network connected?

Edit: No change when using other power cable. Case temperature is 37°C on the bottom and 32°C on the top with ambient temperature of 25°C.