Asus TUF Gaming FX506LX laptop just stuck at random time

[Dreigas]

Hi everyone,

I've got a problem with my Asus TUF Gaming FX506LX laptop. I bought it as a non-working unit it had been completely drenched in a sweet alcoholic drink and was left for a year... When I got it, the motherboard wasn't in terrible shape, but I had to clean a lot of areas—about 1/5 of the motherboard. There was some corrosion, but I managed to clean it up and re-soldered where I saw issues under a microscope.

One of the two primary MOSFETs was fried (PQ33 fried and PQ34 were fine), so while I was waiting for a replacement, I desoldered it and created a short. The RAM module wasn't directly affected by the spill, but I had to replace it anyway as the old one was no longer working.

In short, I completely cleaned the computer, re-soldered where necessary, removed PQ33, and temporarily shorted it (beginning of VA circuit), replaced the RAM module, and the laptop became fully functional! Almost fully...

While I'm in the BIOS, there are no issues. I can leave it for half a day without any problems, but as soon as I start installing Windows 11, it can freeze at any random time (the image remains on the screen, but the computer itself stops responding, the fans slow down after a few seconds after a freeze because the CPU temp going down instantly). I have no idea where to look for the problem now... Sometimes I manage to fully install Windows 11 without any freezes, and everything works perfectly until it freezes.

I also suspect the GTX 1650 graphics card, as it's showing 0.1 OHM on the +NVVDD circuit. (And still have not yet tested it, because when I install integrated graphic card drivers always computer stuck on a black screen, so when I need to reinstall Windows again...) Or just stuck on a random thing... When choosing the Windows language which to install etc...


Thanks for any advice.

[Dreigas]

One more question, is it normal for the FCBGA874 FH82HM470 chip in one corner to have ~70-75 Celsius temperature? Here is one spot on the running motherboard, which become pretty hot...

Adding thermal camera photo.

[mcplslg123]

So you are running it without PQ33 soldered and source and drain jumpered. Right?
If so,this may be responsible for this odd behaviour.
PCh at 70-75 cels is ok.

[Dreigas]

So you are running it without PQ33 soldered and source and drain jumpered. Right?
If so,this may be responsible for this odd behaviour.
PCh at 70-75 cels is ok.

Yes, you are right, I'm using it without PQ33 now. Ok, I will wait while I will get a new PQ33 Mosfet, and then I will try.

[Dreigas]

I have changed PQ33 to the new one MOSFET, but the problem still exists. I have searched for some info on the internet and it seems the same problem has a lot of people...
But some people freeze when watching YouTube with Chrome, and some randomly freeze, like me. Some people fix it with bios updates, but I have the latest version, some people for a while fixes with drivers, and some like me can't fix it at all.
Sometimes I got freeze even when installing Windows and if the computer is running 30min+ I get the PC freeze even more.

I noticed one thing, I think the problem is with integrated intel graphics... Because all the time my PC freezes when installing integrated GPU drivers... But without any problem allow to install Geforce 1650 drivers... Some people can solve this problem with simple things (bios update, drivers update etc), but some can't, like me now...
I tried Debian OS also, and the same problem exists...

Does anyone have any ideas? I can't disable the integrated card by BIOS...

[loopster]

How about giving Windows 10 a try (or maybe even a Linux distro) to rule out any weird OS related incompatibility issues?

[Dreigas]

How about giving Windows 10 a try (or maybe even a Linux distro) to rule out any weird OS-related incompatibility issues?

Already tried Debian Linux, and even on Bios one time was frozen... And Freezing at MyAsus diagnostic program when launched by UEFI... I think the problem is with the integrated video card, my BIOS doesn't have the option to disable it. Because when I installed an intel integrated graphic card always computer stuck on a black screen... Other Drivers I can install without problems if I do not get random freeze... Is there any way to desolder something from the mother to disable the integrated graphic card? Last time when I installed Windows 11 and was forced to use always GTX 1650 instead of integrated I used a PC without freezing for ~10 minutes! It's a big deal now! But when I tried to install Intel graphic card drivers and PC again stuck and need to reinstall Windows now... But also need to turn off updates, because with updates Windows will install these drivers auto.

[mcplslg123]

Seems like iGPU has issues as display getting blank after intel graphics driver install. i'm sure you have tried manufacturer driver also.
If you have all the mosfets/driver ic /pwm related to VCORE circuit,you can replace them(all the components must be replaced at the same time).Sometimes this works but not always.
If you dont have the spares and dont want to buy them as well,then simply remove all these mentioned components ,apply some flux,fresh solder and resolder them.
Might work-may not work.

[Agent24]

You say it was left drenched in a beverage for over a year.

I would suspect there is still residue or corroded connections somewhere.

Run the whole board through an ultrasonic cleaner and hope it starts working...

[Dreigas]

You say it was left drenched in a beverage for over a year.

I would suspect there is still residue or corroded connections somewhere.

Run the whole board through an ultrasonic cleaner and hope it starts working...

yesterday motherboard was fully cleaned in the ultrasonic cleaner, but the problem still exists. Now waiting for VCORE circuit parts while it come and I will try to change it.

[Agent24]

Definitely could be a bad chip then, I've seen where liquid like battery or capacitor electrolyte gets up into an IC and destroys it internally from corrosion etc.

I hope that there is no liquid that's soaked into the PCB substrate and is causing leakage between tracks etc. That is also a possibility depending on the liquid and the duration.

[Dreigas]

Definitely could be a bad chip then, I've seen where liquid like battery or capacitor electrolyte gets up into an IC and destroys it internally from corrosion etc.

I hope that there is no liquid that's soaked into the PCB substrate and is causing leakage between tracks etc. That is also a possibility depending on the liquid and the duration.

We will see soon. One more thing, CPU and GPU were clear, and there was no liquid damage at all, only some discrete GPU MOSFETs had some liquid damage, but they seem ok now. Liquid was 38 degree liqueur Under some transparent keyboard buttons still, I can see it. (I will replace the keyboard if I will solve this problem)