"I switched to Arctic Silver 5 right away and it cools much much better."
That made me laugh for some reason. Makes it seem like you switched when you first got it before turning it on. How did you notice a difference?
Yeah Arctic Silvers probably your best bet. Though mine has an Arctic Cooling make of thermal compound called 'MX-5' or something or other that came with it. Supposedly works better, at least with the heatsink I have, compared with Arctic Silver from reviews.