It depends on what your motherboard supports. Find out what kind of motherboard you have and see what the limit for processor speed is that it supports. If you arnt able to reach the speed you want you can get a new motherboard/ cpu combo off various sites. Pricewatch.com has a pretty nice list of cpu/mobo combos. You might want to do some research on your case as well, not sure how dell works by the compaq I bought had proprietary motherboards so I could not fit anything but their stuff in my case. If this is how your dell case is then you will have to get a whole barebones kit which is a motherboard, cpu, and case all in a package. This will be the worst case scenerio for upgrading your processor. Do some reasearch on your current setup and see just how far you have to go. Dont worry too much, you can get a decent barebones kit for under 300 dollars.