Question Fan stops upon boot, spins fast after a minute or two, stops again, and so on.

[Takap]

When powering laptop, fan turns but stops a few seconds, after a minute it runs fast in 10 or so seconds then stops again. It just alternates with that, HDD running, no display.

 

[mrmike16]

What model laptop?
From that description, it could be quite a few things - Power supply/battery, CPU, RAM, GPU, motherboard. Anything happen since the last time it was working?
Your best bet is probably checking all of the parts.