I always used to use the Processes tab of the Task Manager and the CPU column, (short for CPU Usage). I would click the CPU column header once or twice to list in CPU usage order so that the most usage processes were listed at the bottom.
50-60 processes is quite high for XP although every system is different of course. But I tried to keep mine down to mid 30s to 40.
Identifying what all these are is difficult, but I would first look at BlackViper's XP Services list to see what services you are running, and trim those down to only what is needed;
http://www.blackviper.com/2008/05/19/black-vipers-windows-xp-x86-32-bit-service-pack-3-service-configurations/
That should help remove some unwanted processes. For the rest of the processes, you would need to check each one in Google, and a good place to start is http://www.answersthatwork.com/Tasklist_pages/tasklist.htm
It's time consuming, but it doesn't all have to be done at one go.
Hope that helps.
Mark
When my Windows xp SP3 system slows down, I usually look at the Task Manager to find the resource hog. My question is this- which of the columns is most important? Is it Memory Usage, Peak Mem Usage, Page Faults or I/O reads? On my PC, there are about 50-60 active processes. Since I cannot tell (by Image Name) what these processes are doing, I need to find the culprit. Once I know which resource is most important, I can try ending each (unnecessary) process one at a time.
Suggestions?

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