I bought a RPi 4GB at kubii.fr on the 24th of June 2019, delivered on the 21th of September.
My Pi had a solder problem on the SD card slot, which was loosening.
They offered me a replacement.
The previous (orignal) Raspi had power :
- NOT working with USB-C PD power supplies : Macbook 12" 2015, Macbook Pro 15" 2018, Anker PowerPort Speed+ Duo, Nintendo Switch, LG 32ul950 screen
- OK working with stupid non-USB-C-PD power supplies : As I only buy USB-C PD, I only succeeded booting my June RPi4 with an old iPad mini 3 "10W USB" power adapter (not USB-C nor -PD at all) + a stupid USB<->USB-C cable (of course I know that 10W could be insufficient for RPi4 so I stopped using it since I had no other 3amp power supply... and I did not want to start buying non-USB-C-PD just for RPi...)
Currently, the new (replaced) RPi 4GB I received yesterday :
- works with USB-C PD power supplies : Macbook 12" 2015, Anker PowerPort Speed+ Duo + "USB-C charger cable (apple)", LG 32ul950 screen (with a USB-C non-TB3 cable, plugged on the USB-C-TB3-70W-able port of this screen)
Are new batches of RPi4 USB-C have their PD specs fixed?
Or I am just lucky to have a RPi which could have some of its electrical resistance components damaged and unwillingly fixing the problem?
I issued a, which took 62s to complete (matching a random RPi4 benchmark found on the web) :
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$ sysbench --test=cpu --cpu-max-prime=20000 --num-threads=4 run
I have a funny USB-C multimeter (those that have two USB-C ports, one at each side, and which are able to mesure amperage)
With 32ul950 USB-C-TB3 70W port I got :
- 5V 0,8 Amp at boot
- 4,83V 0,74 Amp once logged, idle
- 4,78V 1,13 Amp during sysbench
- "stress-ng --cpu 0 --cpu-method fft" yielded 4,70V 1,47 Amp
(yes, I know that I should expect a CPU bug or damage with under 4,75 V, which are undervolted)
The Anker USB-C PD adaptateur yielded (this Anker is labelled at 2,4 Amp at 5V, and is one of the best-rated PD adapter by the Google guy which made the spreadsheet of USB-C cables&adaptaters) :
- 4,92 V 0,74 A once logged, idle
- "stress-ng --cpu 0 --cpu-method fft" yielded 4,86-to-4,90V at 1,40-to-1,47 Amp
So, RPi 4 USB-C PD are fixed ?