you do not need very much. as far as i know they sell AS5 in two sizes i bought the bigger one, which is good maybe for 20 computers, thats just a guess. again you dont need much so use it and you should see at least 5 degree drop since your using stock cooling. but that being said remove the old thermal paste with at least 91% (i have used 70% before not a big deal) alcohol. wet sand your chip down too while your at it, its called lapping helps with about 1 or 2 degrees more. Google "lapping" for further instructions, its not a big deal doing this.