"Samsung NP-N145+ - System Shuts Down Randomly"
By Ron Stultz
21 March 2014
Summary: although central processing unit (CPU) chip in the NP-N145+ is fairly small and should not generate a lot of heat, all modern CPU's will shut down the system if it gets too hot. The solution is to renew the thermal grease between the top of the CPU chip and the attached heatsink.
Background:
Samsung NP-N145+.
System would not turn on and thus taken apart to determine problem.
While motherboard exposed, renewed thermal grease between CPU chip and copper heatsink and fan.
It is not uncommon for a laptop to experience random system shutdowns because the CPU chip overheats and commands a system shutdown to protect itself from thermal damage.
A CPU chip will overheat: if the fan does not turn when commanded to or is full of dirt or dust or the thermal "grease" between the top of the CPU chip and the heatsink/fan is so dried out that there is no real heat transfer from the CPU to the heatsink/fan.
Before taking your NP-N145+ apart, try to determine if the fan area is clean of dust and that it is turning after the system has been powered long enough to randomly shutdown.
If the fan is not turning, you will have to replace the combination heatsink/fan. The fan for the NP-N145 is available on eBay. Replacement is all part of renewing thermal grease, so below is applicable.
How to renew thermals grease:
Unhook the fan from the connector mounted on the motherboard.
Remove the (4) small Phillips screws holding the fan and heatsink in place.
Lift up the cooper heatsink/fan.
The image below shows the cooper heatsink/fan of the NP-N145+ removed from the motherboard with the area that sits on top of the CPU chip marked in red.
Using a tissue, remove all dried thermal grease from the bottom of the copper heatsink and the top of the CPU chip.
Using high quality thermal grease available at Radio Shack, computer parts retailers, eBay and other Internet outlets, place enough thermal grease on the CPU chip top so when spread, it covers the entire top of the chip. DO NOT USE TOO MUCH OR TOO LITTLE.
Place the heatsink/fan back over the CPU chip and slowly lower it into place.
Reinstall Phillips screws holding heatsink/fan to motherboard and down on top of CPU chip.