R50 dies

[thomaslp]

Hi,
I am struggling with a R50. It shuts down as soon as i touch it. I thought that it was a GPU issue so I have made a reflow twice now - and I am following instructions found on this site and I am using a IR thermometer. First time I heated it up to 230 C and the second time I took the chance and hit 250 C. But still the problem is there. I am quite sure that the reflow is done correct. I did it before on 5-7 T4X machines with great results.

Could it be a loose connection somewhere else. I have noticed a low bipbipbipbipbip noise as soon as i plug in the power supply. It comes from a coil marked 6r8 in the lower right corner of the mainboard. I tried applying a little pressre to this device but no change. I also tried to plug in the battery. Now I do not hear the bip noise but the problem is the same.

So far I have seen GPU problems making the laptop monitor black but the fan has always kept spinning. In this case the laptop simply dies and I need to unplug the power for a few sec. and then I can try again.

Any suggestions anyone?