Solved! ASUS notebook no boot but power light is on and fans spins

[alette2]

Hello everybody,
I have this ASUS x54c that wasn't working, so i bought a new motherboard from AliExpress and tried to revive it... but:
when I press the power button only power LED lights up, then after 20-30 seconds the fans start spinning. The screen is black, same results connecting to an external monitor.
The keyboard doesn't seems to work

• I took everything apart, cleaned and carefully re-connected together.
• I switched the two 4gb ram sticks, then removed one to see what happens, than switched again
• I used the old trick of pressing for 30-60 seconds the power button
• Checked with the multimeter for any bad connections
• checked for any bad capacitor
• changed the CMOS battery (waiting at least 3 minutes before reconnecting the new one)
• tried to boot the PC with the minimum components needed
• tried to boot only with supply cable, then only battery, than both
• prayed for a while

Other things that may help:

• The PC has an Intel processor with nvidia graphic card, both soldered directly on the motherboard
• I tried to use a usb keyboard and I was able to light up the CAPS LOCK LED when pressing the relative button, but only once
• only once the block numb LED was on

Nothing did work, I'm in extreme pain.
Someone can help? I don't want to send it back because is a pain you know were... thank you

 

[AlHuneke]

A couple of questions:

• What was the machine doing before that made you suspect the motherboard was bad?
• Did you use ESD (antistatic) precautions when you had the unit opened up? I get nervous when I see people mention "cleaning" as that is a good way to blow something up. Actually touching anything inside can cause damage from static discharge (even if you can't feel a spark)

Did you do the function key sequence needed to active the remote monitor when you plugged that in (assuming you have to do that on your machine--I do on mine). Doing this with no visual feedback is difficult.

Assuming you can access your router admin page, you can see if the laptop is talking to the router. If it is, most of the motherboard must be working.

Assuming sound is turned on, try plugging in a USB stick and see if you hear anything. If so, again, the motherboard must be (mostlly) working.

 

[alette2]

A couple of questions:

• What was the machine doing before that made you suspect the motherboard was bad?
• Did you use ESD (antistatic) precautions when you had the unit opened up? I get nervous when I see people mention "cleaning" as that is a good way to blow something up. Actually touching anything inside can cause damage from static discharge (even if you can't feel a spark)

Did you do the function key sequence needed to active the remote monitor when you plugged that in (assuming you have to do that on your machine--I do on mine). Doing this with no visual feedback is difficult.

Assuming you can access your router admin page, you can see if the laptop is talking to the router. If it is, most of the motherboard must be working.

Assuming sound is turned on, try plugging in a USB stick and see if you hear anything. If so, again, the motherboard must be (mostlly) working.

Sorry but I didn't understand the first question, I bought a new motherboard because the original one was fried, but the new one is giving me problems.

I use a plastic pad under the notebook when working on it. No gloves. I've used a compress air can to clean

Yes, I did the button sequence without luck

No I didn't tried checking the router. I will try to connect it via ethernet cable and then I'll verify

Yes I plugged in a USB stick but no sound

(Thank you by the way)

 

[AlHuneke]

My first question was asking what was the machine doing to convince you the motherboard was defective in the first place? Is the replacement MB acting the same way?

Having the machine on a plastic pad while working on it is unfortunate (unless the pad is conductive and grounded). Suggest you read about ESD protection measures (look at couple of different articles as there is misinformation out there). Compressed air for cleaning is likely OK. A bristle brush on a vacuum is not.

I don't really have any more troubleshooting advice. It is possible you damaged the MB when you installed it or possible that it was defective when you received it. ESD precautions are important even it they are often ignored. Eventually you get bit. Maybe that happened. Sorry. Or maybe it isn't the MB at all.

 

[alette2]

My first question was asking what was the machine doing to convince you the motherboard was defective in the first place? Is the replacement MB acting the same way?

Having the machine on a plastic pad while working on it is unfortunate (unless the pad is conductive and grounded). Suggest you read about ESD protection measures (look at couple of different articles as there is misinformation out there). Compressed air for cleaning is likely OK. A bristle brush on a vacuum is not.

I don't really have any more troubleshooting advice. It is possible you damaged the MB when you installed it or possible that it was defective when you received it. ESD precautions are important even it they are often ignored. Eventually you get bit. Maybe that happened. Sorry. Or maybe it isn't the MB at all.

Ok, thank you anyway