Getting In Too Deep

Symptom 1:  Unit runs for a while then turns off Symptom 2:   Unit turns on, turns off immediately This unit arrives after another tech had attempted repairs.  Numerous screws missing from base and incorrect screws used in reassembly.  Complete tear-down and disassembly. After powering the unit up, I noticed that the heat sink copper was discolored [darkened] which is a sign of high heat.  Upon close inspection I noticed a kink in the heatshrink material covering the wires for the fan wires, so I strip back a portion of the insulation and the red wire was broken, and the black wire was only 2 strands. Yellow and White wires were OK.  Rather than replacing the fan (which is in short supply, and costly) I repaired the broken wires with solder and insulating them so that they would not short each other or the frame of the HS fan, which is negative ground. Screw also missing on the exterior frame that holds the heatsink downward onto the base, th...

A DV9208 arrived with overheating problems. Luckily it was caught before it started generating additional issues with the GPU. Symptoms: Unit would overheat, cause shutdown/off without notice. WIFI would turn off Cause: Heat sink vents 75% blocked, so insufficient cooling was the culprit. Repair: Disassemble unit, disassemble heat sink, clear vents. Problem #2 was a little more different. Because the Southbridge would also overheat, causing loss of contact on solderballs. Solution: Clearing the lint from heatsink will remedy issue with overheating/shutdown. Since no drive arrived with unit a substitute drive was used to run system for several hours, then turned off, and test again.  I do this about 4 tests so that nothing happens when it gets back to the customer. Aluminum heat transfer pad for CPU replaced with copper pad.  The pad from HP is only ok, but many times the CPU gets so hot that the Aluminum breaks down and sticks to the CPU. Not providing a...