Lafite II Wake Up Issues

This has been an issue ever since I got this laptop. Occasionally on waking, the fan will blow very powerfully, and the system reacts very slowly to anything I do. When I look at the Task Manager the CPU seems to be maxed out at only 0.37GHz - it cannot go any higher.

I can solve this issue by making the laptop sleep, and waking it up again. But I'd really like to know the underlying cause so I can fix it once and for all. Any help would be greatly appreciated. Cheers!
 
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