@robi62 About your issue with the CPU, the P8600 runs at 2.4 GHZ. Some CPUs are not exact, as mine runs at 2394 MhZ. Is it a big issue like it running at 1.6 GhZ?
@bootxy When you turn the system on, hold down fn+LShift and type 15324. The press fn+r. This takes you to a hardware monitoring bios setting display, where we can see your temps, fan speed, CPU throttle, power throttle. All these could contribute to the issue of the random shut downs.
Report back, and I'll check your issue.
Sorry for not being able to help people, I am hardly on anymore, except for a major OS release or something. Feel free to PM me and I can sorta help xD