Questions about rpm constant/max and sensor based usage

[powermonger]

Hey!

I just got my MacBookPro8,2 back from repair. I got the broken graphic chip (screen glitches/crashes) exchanged, which seems to be a very common problem for this type of MacBook.

For a longer life of the hardware, the service team also encouraged me to increase the fan's rpm after I told them my concerns about heat and possible source of the problem.

Now I'm trying to find the optimum settings for my MacBook and got some questions - would be awesome if someone can explain this to me.

Constant Method

If I would use a constant speed (let's say ~4000), would this mean that the fans will still go up if needed? I'm not sure how to test this. Sure, it says: min 2000, current 4000, max 6200. On the other hand, the 4rth column says: Constand Value of 4000, so I'm not sure what applies.

Sensor Based

I'm thinking of using the sensor based method. However, I can only pick 1 sensor per fan. What if a 3rd sensor I didn't pick goes up? Doesn't sound too good to me.

Also: I don't know which fan (left or right) is better for cooling certain parts. Is the left one better for cooling the gpu or is it the right? Does it matter at all?

Thanks for any advice in advance. : )