HP elitebook 840 G9 Burintest failure

[zamine]

Hi

i purchased 2 days ago a used HP elitebook 840 G9 with i5 1245u inside and 16 gb ddr5, it comes with a suposed OEM 65w type C charger but the visual quality is unconvincing.
before payement at the store , i lunched the quick test 3 overall that passed without any problem.

at home, with the charger plugged in, i lunched the Max CPU temperature, it immediately displayed temperature failure (100° threshold exceeded), same with CPU coverage test but both achieved the 15 minutes duration.

during those tests, the Type C charger was very hot to the point that it was nearly impossible to keep it in hands…!

i tried the 24H with charger plugged in and it was terminated after 1h39 only, with the same temperature failure problem.

i tried the Max CPU temperature without the charger (only on battery and the temperature was around 65° all the time and it hit 70° only in the first seconds) and there 0 errors after the 15 minutes duration of the test.


So the first thing that it's clear to me that the charger is a problematic (fake or bad one) but i don't know that if it's responsable of the thresholed exceed problem ! Unfortunately i don't have another charger to try the burintest tests with it.


this is some caps of the 24H test failed with the charger plugged in.




i would to know if this problem is due only to the bad charger or a problem in the my HP elitebook fan's system or the processor itself ? i know it's a U model but and the fan system isn't optimized for long sessions of heavy work but can't a such machine (old or completely new ) run a 24h test without temperature and threshold exceeded problems?


all opinions and advices are welcome

[David (PassMark)]

Many (most) laptops change their power profile settings when on battery power vs mains power.
Typically they run at higher clock speeds when on mains power. Higher clock speeds means more heat. So the CPU being somewhat hotter on mains power is normal. Also while the battery is charging the battery will also get warm, adding to the heat load in the machine.

This is a fairly thin laptop. It might not have any fans?

100C is the limit for this CPU. It should automatically start to thermally throttle at this point.

It is very hard to cool thin laptops well. But nevertheless it is kind of bad design. Maybe they should had added 3mm to the thickness and added better cooling.

You could probably edit the power profiles in Windows to restrict the max CPU power to get it under control.
But if course the CPU will run slower.



Charger might also be not be very efficient if it is too hot to touch. Fortunately it is type-C however, so there is a huge amount of choice if you wanted to replace it. Anker 100W would be a good choice. (65W should be enough, but 100W is more flexible, as you can charge phone and laptop at the same time).

[zamine]

thanks for the response david

if the throttle issue is due to the laptop design it's ok for me but since the charger seems problematic and the pc is a used one i was worried about a faulty pc causing a abnormal throtle, especially that i read that some users did 20h tests or more without problem.

it's true that it's a relatively thin notebook but for a professional notebook (elitebook series) i expected a better result, there's some picture of the rear and the fan system.

[David (PassMark)]

It is certainly possible there is a fault with the fan (or fan speed), or blocked vents, or poor contact of the heat pipe to the CPU.

Can you hear the fans running, do you get hot air coming out of the machine when it is under load?
(hot air is good, in the sense that it shows the cooling is working)