The RK3399 Overclock/Undervolt/Voltages Thread

[generaleramon]

Sorry, my question wasn't precise enough...  Was the red LED next to the barrel port blinking while you were compiling the kernel source?  Blinking red LED indicates that the BQ24171 is overheating, no longer charging the battery.

You're right, PineBook Pro cannot take more than 3 A at 5 V from any of its two power inputs.  Please, have look at this thread, which describes the limitations of the PineBook Pro's battery charging circuitry, together with some possible solutions.

yeah i think i noticed the red led blincking sometimes i'll keep an eye on it.
Thanks for the info regarding the power ic, but i think i'm gonna keep it limited to 3A to preserve battery health in the long run, sometimes i charge it with a usbc cable and a 1A charger.

[dsimic]

It would be great if you could perform the compilation again, while monitoring the status of the red LED next to the barrel port.  That way we'd be able to see if the heat soak has been resolved by your modifications, i.e. whether the overheating issue of BQ24171 still persists or not.

As a note, one of the design flaws of the power circuitry in PineBook Pro is that the entire laptop is always powered by the battery.  If a charger is connected, it serves only to charge the battery.  As a result, the battery still discharges when a charger is connected, if  the total power draw of the laptop is over 15 W.

I have also been thinking about modifying the power circuitry so the laptop actually takes power from the charger, if one is connected.  However, this stopped because I've been unable to obtain a PineBook Pro that would be used for testing such hardware modifications.

[dsimic]

I've accidentally stumbled upon some RK3399 specifications you actually asked for.

Please, have a look at chapter three (page 65) of the RK3399 datasheet.  It provides a list of minimum and maximum values for the CPU and GPU supply voltages.

[generaleramon]

I've accidentally stumbled upon some RK3399 specifications you actually asked for.

Please, have a look at chapter three (page 65) of the RK3399 datasheet.  It provides a list of minimum and maximum values for the CPU and GPU supply voltages.

i already checked that, but those are "recommended operating condition", so those are not really phisical min-max values.
btw, i started compiling and watching youtube 45min ago, SoC temp between 55c and 65c, no red led blinking, and surprise surprise, the battery went from 75% to 80% at the moment

[dsimic]

That is great news!  If the BQ24171 hasn't started blinking the red LED in 45 minutes, we can be almost certainly sure that resolving the heat soak issue also fixed the battery charging issue under prolonged high CPU load.  As a comparison, the red LED has always started blinking in less than 30 minutes on my unmodified PineBook Pro, while doing a "make -j6" in the Linux kernel source.

[generaleramon]

Today i managed to squeeze out another 100Mhz out of the A72 cluster. 2184Mhz@1325mv(Linpack-HPL Stable), i needed to connect a laptop fan to a usb cable and run it at max speed, barely managed to keep it under 75c. The thermal transfer between cpu and backcover is not optimal, i'm gonna order some 1-1.5-2mm copper shims and a good quality 0.5mm pad, i want those extra 30Mhz and max out the SoC at 2208Mhz. This toy it's starting to run fast

[dsimic]

You're really serious when it comes to overclocking.   Keep up the good work!

As a suggestion, you might want to try performing an "open-heart surgery", in the sense of removing the back cover of the laptop and attaching temporarily a passive or active heatsink directly to the RK3399 SoC.  It would be interesting to see how far the RK3399 can be pushed with a high-end cooling solution.

Have you kept an eye on the red LED next to the barrel port, while doing the stability testing of this overclock?  Was the battery discharging while running the stability tests?  As you can see, I'm all about testing out the effects of applying additonal cooling to the BQ24171.

[generaleramon]

i FINALLY received the copper shims i ordered, i'm gonna report back as soon as i have some data

EDIT: I can tell right away that the new 2mm shim + 0.5mm pad works great. Youtube + 2 flac encoding and the cpu still remains below 75C passive. i'm gonna find out soon what i can do with active cooling

[dsimic]

Sounds good!  It is expected that reducing the thermal pad thickness, using a copper shim, would result in better heat transfer.

[coetzeesg]

I was wondering if you could describe the thickness of the shim + pad to touch the bottom panel, and the pad thickness being used to connect the other ICs to the spreader around the cpu. I'm trying to buy some thermal pads + shims in anticipation of a new pinebook pro arriving shortly.