I've never put any thermal paste on my cpu and I've had it for about a year. No problems. Should I have? I'm getting a new heatsink in a few days, so should I just go ahead and order some?
We do recommend thermal paste, although most heatsinks come with a small layer already, it isn't as good as separate tubes you can buy. I recommend Arctic Silver as thermal paste, when appying only apply a very thin layer and you may get a small antistatic card with the paste to spread it thinly over the die of the CPU. Don't put too much as it tends to have the opposite effect.
Thermal paste is necessary as the pad you probably have is a one-time use and can't be reused. You'll want to clean off the cpu with some isopropyl alcohol and let it dry before applying new paste. Now, you don't want to glob it on. There only needs to be a thin layer on the core, or, if it's covered by a heatspreader, the surface of the heatspreader that meets the heatsink. The reason you want a thin layer is that the paste fills in the microgaps in the heatsink. No matter how smooth the heatsink is, the microgaps will still exist, and to get the best transfer, you'll want to use paste. If you glob it on, it will act like an insulator for the heat, which is the opposite effect you want to have.
Sure you don't absolutely have to but it's a very small investment that will increase the life of your processor and improve resail value too (saying you didn't use thermal paste wouldn't instill a lot of confidence in your potential buyers just for example).
Could you use soder in stead of thermal paste? Obviously, you would not be able to seperate the cpu from the heatsink without damaging the cpu, but would it give decent performance?
I don't think you could use solder because of it's low melting point, it'd be constantly melting and solidifying. Really, go out and grab a $3 tube of thermal paste and your set.
