Heatsink too tight causing computer to shut off?

[Crucible1001]

So, I got this laptop that was having trouble shutting off randomly when moved or shaken.

After testing every single piece of hardware I pushed on the heatsink directly while the computer was running. It would shut off every single time I pushed on it right on the cpu. I loosened the screws just a bit, and it won't happen anymore moving the laptop.

The question is, how can a heatsink on too tight cause the cpu to stop working? Also, is it okay to have the screws loosened?

Before I only had to barely tap the plastic case where the CPU was located to cause it to shut down. Now It won't unless I push hard on the heatsink directly.

 

[Joe Average]

If it was that tight, there's a good chance it's caused a micro-fracture someplace in the CPU itself or the solder joints someplace attaching the CPU socket (the whole piece) on the mobo. The heating up-cooling down cycles do tend to degrade solder joints over time, and if the laptop happened to be moved at some point when it was actually "running hot" that could cause those micro-fractures to occur.

They're so small that it doesn't take much for the connection to sever and wham, instant problems.

If it's not happening anymore because you let up on the pressure by loosening the screws a bit, you're ahead of the game and you can stop beating up your CPU.

 

[DanNeely]

One other possibility might be that the over tightened heatsink was applying a sufficiently asymmetric load that the limited flex in it wasn't sufficient to keep it in full contact on the lightly tightened side.