When overclocking my GTX285..

Hi,

I just got a few things I'm unsure of, after getting my new GPU, that I would love getting cleared up.

1. Is the core clock etc supposed to go up and down depending on whether I am using a 3D application or not? According to GPU-z the clock speeds changes. Can I be certain that it will increase the clocks at the right times?

2. I intend on using rivatuner to play around with the card. It seems pr. standard it always just does 40% fan speed, but with rivatuner I can make profiles that loads higher fan speeds at higher temperatures and vice versa - is this advisable?

3. When increase the different clocks, should I leave the 2 out of 3 at standard, when clocking the third, until I start getting artifacts/errors, and then find each clock's max one at a time, that way?

That's all I can think of right now. I hope someone can help me out a bit

Thanks in advance,

Ottosen