Read arctic silvers own instructions...
http://www.arcticsilver.com/arctic_s...structions.htm
You should spread it out over the die, before putting the heatsink on.
I've got a Barton 2500.. with the stock retail HSF, it would idle mid 40's and under load mid 50's.. sometimes over 60 if the missus had the heating turned right up..
I bought a Thermaltake Silent Boost cooler (the Athlon one, theres 2, one for athlons, one for AMd64's). Now I have it overclocked to 3200+ (2.2ghz), and it max's out at 50 under load. Sometimes alot lower depending on house temperature..