I can't remember what the original post about this problem said, so I'm just going on the subject heading. I have found that many times when a system runs perfect on start up and then begins to slow down as it is left on longer and longer, there may be a cooling problem inside the machine. Maybe the mobo or the processor is getting to hot; maybe a fan is out. Systems definately slow down when the inside gets to hot.
As I said, I can't remember the original post, so I'm just going on the subject. If I am way off, ignore me..lol.
Hope you find a solution.

Neal Collins
A+ Certified Technician

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