laptop overheating problem

[amp6n]

I recently replaced the hard drive in my laptop because it was having problems starting (it would get to where it checked the drives, then continuously restart).  After I did this, it now starts and is usable but gives a "fatal overheating problem" error.  Trying to fix that, I added some silver thermal compound between the heatsink and the cpu, but I’m still getting the same error.  I haven’t been using it, so I’m really not even sure if the laptop is actually overheating, or if it just thinks it is... Anyone have any idea what the issue might be? The laptop is a toshiba satellite s45-a151 if that helps anyone...

[Anodoin]

Are there any obstructions to the airflow, such as dirt, dust, the placement of the laptop itself, etc?

Is the fan working properly?

Did someone fiddle with the BIOS and set the thermal shut-off to a lower temp?

[Calum]

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