hp g72 bs52sf replacing motherborad shutdown at 10s after starting

[jeanlucferre]

hello,

on a laptop hp g72 b52sf i replaced the motherboard with exactly the same ordered with aliexpress..I kept all the other componants : rams, processor, fan...

Now when i starts the pc a shutdown occurs after  time of 10 seconds...whatever the starting process may be on os or bios...

The fan starts correctly and all stops later. When i remove the rams the pc don't turn off but nothing is visible excepted caps lock and ver-num keys which blink.

during this short time it's not possible to starts other softwares even on boot usb starting mode.

Placing the processor on the motherboard i expand thermal paste (perhaps toomuch); i redo several times the process but alwyas with the same result.

in the bios insyde20 re.48 there is not advanced menu to control thermal or fan settings.

if someone can indicate me how to make my researchs orwhat to do, i will be very pleased?

thank you in advanced for your answers.

jeanluc.ferre

[Huffer]

If you replaced the motherboard and got all the screws in the right places and got everything hooked up and the system will not fully POST it is almost certain you got a bad motherboard. I am a bit concerned when you say you may have over applied the thermal compound. It is possible to cause a short in the motherboard if you got compound onto the circuits. 

[BeemerBiker]

As @Huffer stated, the system needs to post.  Is anything shown on the display?  If you tap the ESC key can you bring up diagnostics?

What what the original problem with the laptop?

If you put your serial number in the below site, does the motherboard part number match the one you bought?

https://partsurfer.hp.com/partsurfer/

[jeanlucferre]

hello,

thank you for your answers...

when i press esc i enter in the start menu of the bios, but the pc turn off before i can activate and entirely execute the diagnostics.

i can boot on usb boot software like hiren's boot or linux cd but the pc turns off before the execution...

Sometimes when i start on the os w10, the system opens the welcome screen, but i have not the time to do something before shutdown.

in the same maner, it's impossible to update the bios, the system shuts off before complete execution.

the first time i launch the system after a period of rest, the connexion stays 20 seconds, but later for the following trys the shut down occurs more rapidly.

on the display i have not error messages, and for some seconds the display is correct.

With the laptop the original problem was water fallen on the keyboard, the power light then didn't lit and nothing happened.

Now after replacing the motherboard the power led light works perfectly.

When i remove the rams, the system starts, nothing is displayed, and then there is no shutdown, the fan turns slightly, the keys capslock and ver-num blinks...

I hope these last precisions will allow you to help me.

Thank you for your contributions.

Jeanluc.ferre

[BeemerBiker]

Turn off, but leave plugged in and let the battery charge up. 

Disconnect the charger and press the power on button.

If it works then a problem with charging.

The 10 and 20 second problem you describes does seem like the CPU overheating.  Possibly the bios is not designed for the CPU and gets the wrong temperature.  Possibly one of the fan(s) is not reporting its RPM correctly and the system thinks no fans are running.  

This is much older system and difficult to debug.  If the display is good you might consider obtaining a working system that has a damaged display.

Good Luck!

[jeanlucferre]

Thank you for your answer...

a few days ago, i tryed with another charger and that was the same thing...i tryed also with a usb keyboard after disconnecting the in place keyboard and the same default occured.

The serigraphies of the ancient and new motherboard are exactly the sames, this last one is well suited...

The bios of the new board is Inshyde20 rev .48...and i didn't find means to make appear the hidden advanced menu settings in order to control thermal and fan settings...the life of the system is too short to launch a bios update, it's too dangerous to launch this update with the shutdown that occurs.

Before changing the board it seems i have read something about a manipulation to execute on the bios, but i don't remember what it was and i could'nt find back what it was.

For me this problem is either a thermal one or a bios one.

Perhaps cleaning all the thermal paste and installing a thermal pad would be better.

Thank you for all, and waiting for your new suggestions.

jeanluc.ferre

[BeemerBiker]

On more than one occasion I have held my fingers down on a CPU and powered the motherboard up to determine if the CPU was working or not.   On older desktop systems with socket  1366 it take only 5 seconds to feel heat and the power needs to be shut off immediately.

 This would be hard to do on that laptop as I recall a disassembly video for g72 showed the CPU on the other or "back" side of of the laptop frame and not available to be touched easily.

I once forgot to remove the plastic protective film covering the copper on a liquid cooler and the desktop worked for several days but ran hot before I looked into the problem and removed the plastic protective film,.

Does your laptop have a secondary GPU such as an NVidia mobile chip?   Perhaps that chip requesting a shutdown due to temperature.  If the motherboard chip surface is available you could use electronic freeze spray to keep the chips cool long enough to get into the bios.  That would required several hands to do properly.

[jeanlucferre]

hello,

Thank you for your contributions...

There is not another gpu, the main gpu is on the same chip that the cpu...

For me it's a problem of fan or bios settings. (because i made several times the operation of lying thermal paste).  

Finally for some days i lead the laptop in a repair technician shop because i am not able to do myself better work with the thermal paste...i hope he could do better work.

This technician told me that the hp bios requires an administrator password before making appear the advanced settings...thing i didn't know and he didn't speak of that when i phoned him.

When the laptop will come back, i will try your suggestion of refreshing the cpu with freeze spray.

Thank you for all and have a good day.

jeanluc.ferre

[jeanlucferre]

Hello,

my laptop came back from the technician but always with the same problem.

When i compare the old (broken) and the new motherboards i noticed that though they had the same printed circuit references they are not exactly identical. the new one has a vga ic chip (i supposed it's a graphical chip) and a thermal sensor unit that i didn't find on the old.

perhaps the shutdown is caused by a thermal problem on another chip that the cpu-gpu one.

Following my exam i noticed that there is not thermal pad on the graphical chip...but as i use the old heatsink cooling module there is not place for adding thermal pad in order of cooling this chip. 

perhaps i had to order another cooling module or exchange the motherboard i receveived from aliexpress with a new one that would be completely the same that the old one. Finally it's not a problem of processor overheating though several times the 90d error occured.

Thank you for reading me and if you have any suggestions i will be very pleased.

jeanlucferre

[Huffer]

Yes. Motherboards with dedicated video use a different heatsink than ones with integrated. If you run the computer with an incorrect heatsink not covering the video chip I would expect it to do just what you are seeing.