c650 very slow

[wilham]

I've resored to factory settings twice - still very, very slow. Any ideas?

 

[nukemaster]

Have you checked the cpu temperature with something like HWmon or CoreTemp? If the cpu gets too hot it will throttle and cause the system to slow down quite a bit.

If the temperatures are very high, you will need to clean the fan/heatsink(s) on the unit. This may involve dis assembly of the unit.