Lots of times, possibly most of the time, my computer lags for seemingly no reason. I can be using little as 15% or less of my CPU, and around 50% of my RAM (I've honestly never seen it go above 60%) but my computer will be incredibly laggy.
The one idea that came to my mind was my read/write speed to my HD, but this still happens while I'm doing activities that should not require any reading or writing to the Hard Disk.
I know that viruses and other such things can often be the cause of computer slow-downs so I did some virus/malware scans with multiple programs, all of which came up blank.
This is an all-around lag. It can be programs being slow, music pausing and skipping, programs becoming unresponsive, and even my mouse just freezing up and then jumping across the screen, or moving so slowly that it feels like I'm dragging it.
(Technical Details: Toshiba Satellite computer, Windows 7 OS.)

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