usually it doesnt use too much, but with it enabled u will notice huge hdd activity and like 50% of the cpu bein used for about 10 or 20 secs every so often when it decides it wants to index some stuff and its really annoying when im doing something and my pc slows down. type services.msc in the run box and go down to the indexing service and properties and stop and disable it. there is also like 20 other ones u can disable safely that u dont use that running slowing down ur computer for example the portable device serial manager or whatever which gets the serial number from a digi camera or whatever it does, needless to say i dont want that running when i will never use it taking up resources