Condensation can [will] form which would short out the processor/mobo and kill either/both items. That is, if not done perfectly/correctly. If you can get your processor to run at ambient at idle, and under 10C over ambient under full load, you're doing better than a ton of people. My [personal] goal is to get my processor to idle at no more than 5C over ambient and have no more than a 10C increase when under load. I'm not there yet, but I hope to be soon, without dumping a small fortune on system cooling.