HP 640 G2 something is damaged

[m2farid]

Hi to all

This is my son's pc.
When connected to the dc it powers on It self without pushing the power switch and after few second the fan go to hi speed. I look the motherboard and I see that there was something wrong. Please see attached picture. Could you please help me repare it if this is possible as there is no much technicien where I live.

Many thanks for your help.
Farid

[mcplslg123]

Re: HP 640 G2 something is damaged

Thats a capacitor which is completely burntout. You need to desolder this cap first and then check to which pwm is that cap connected. Most likely ,that pwm+mosfets if any connected to that circuit -they all need to replaced.

[m2farid]

Re: HP 640 G2 something is damaged

Thats a capacitor which is completely burntout. You need to desolder this cap first and then check to which pwm is that cap connected. Most likely ,that pwm+mosfets if any connected to that circuit -they all need to replaced.

Many thanks but I am not good for this could please guide me how to do that with a little picture.

Thanks

[mcplslg123]

Re: HP 640 G2 something is damaged

Do you have hot air desoldering station+a good solder iron??

[m2farid]

Re: HP 640 G2 something is damaged

yes I do have a solder station with hot air and solder iron, flux and iron wire

[mcplslg123]

Re: HP 640 G2 something is damaged

What is the mb code?? Schematic available?? Proceed to remove those burnt caps first. Apply flux on that area, put some solder with soldering iron first and then apply flux again and use hot air gun to remove them one by one. Once removed, clean the pads and if necesaary re-build the pads and proceed to measure resistance on those caps.

[m2farid]

Re: HP 640 G2 something is damaged

Many thanks, I will try when I have time. thanks again

[Anton K]

My model is different, but I believe it makes sense to share this in this thread. I found similar damage on my 650 G2 on the CIRCUS-6050A2723701-MB-A02 board, and I’m leaving these photos here.