We don’t say “don’t try this at home”, but the way [Troy] Bringing an expensive (but not under warranty) laptop back to life It’s interesting, even if it shouldn’t be anyone’s maintenance work plan A.
It started with a friend’s Alienware laptop, which can only boot to a black screen and get Very It was very hot during the process. With the help of a thermal imager and some schematics, [Troy] One of the MOSFETs that can be seen very close in the power supply seems to be the culprit. It seemed a reasonable way to replace the power MOSFET with replacement parts, so he took the hot air rework station to start work. But this is where the problem starts.
The desoldering process is far from clean, partly because the laptop’s multilayer PCB has excellent thermal management, and the speed at which it absorbs heat is almost the same as [Troy]The heat gun can put it down. It ended up being a messy job that damaged some pads. Therefore, the prospect of welding on alternatives is not optimistic.But looking at the schematic and thinking about the situation gives [Troy] An idea.
According to the schematic diagram, two MOSFETs (at least one of them has failed) have parallel counterparts on the other side of the circuit board. This is usually done to increase the capacity and spread the heat load to a certain extent.However, based on the current calculations on the schematic, these parts are expected to handle a total of about 20 A, but the data sheet shows Each The MOSFET can easily handle this current (as long as the heat dissipation can keep up.) In theory, notebook computers do not need additional capacity.
Now that the faulty component has been simply removed, can the laptop “work”? [Troy] With his friends [Mike] They were willing to give it a try, so after doing their best to clean up the mess, they opened the laptop, and to their surprise, everything worked fine! Some intensive gaming stress tests show that the heat dissipation problem is a thing of the past.
Simply removing one part may not be the best overall repair strategy, but like shrinking it by simply cutting the hot air rework station in half, it is difficult to argue with the results.