The i3-370M has 4 cores total: 2 physical + 2 virtual which is why Qimage (and Windows) reports 4.  That laptop may not be up to the task of multithreading.  It sounds like it could be overheating, causing a shutdown.  What I would recommend is this:

- Go to Edit, Preferences, Multithreading
- Set both "Print Processing Threads" and "Image Processing Threads" to 1

Regards,
Mike

I would go with a single thread because if that works, it gives you more information.  If that solves the problem, try two threads.  Better to rule it out first and then go for more if a single thread works.

You have 4 logical cores as reported by Windows which is why Qimage reports 4 cores: it is telling you that running 4 threads at once is the most efficient (fastest) because the operating system and the software running on that operating system is able to utilize the CPU as if it had 4 cores.  It doesn't matter that, in reality, 2 of the 4 cores can't operate completely independently from the others.  They will still be able to process some machine code as 4 simultaneous operations, hence why we want to see/use 4, not 2.

Unfortunately if your laptop physically shuts down, it's cooling system may not be up to the task of running all (logical) cores at 100%.

Mike