Without having more information about your disk i/o speed and chipset, it's almost impossible to say.
Have you checked what processes are running, when this slowdown occurs? What is taking up your CPU time, if you do a Ctrl-Alt-Del and look at the task manager?
like i saied my friend s have the same problem and our only same point is i5-2500k. but if it s help i ll give you some info about my system.
cpu: i5 2500k
motherboard: asus p8p67
hdd: wd 1 tb caviar blue
operating system: windows 7 64 bit
and when system slowing down there is nothing can do that except setup in task manager i already checked it.
isn't there anyone who have any ideas about that or you are just ignoring
What tab are you looking at, in Task Manager?
i looked all the tabs thats not about that when i am using the hdd which have os on it computers slowing down. if i am use another drive there isn't any problem i think it's a hardware problem because i am not the only one who have it. i think it's structural problem of i5 2500k cpu.
A slow hard drive wouldn't indicate a structural problem in the CPU.