I'm looking to buy a h70 soon but I'm really worried about how I will fit it to my case. I have a Silverstone Raven RV02 case. I'm just worried on how and if it will fit at the top of the exhaust fan. It also says the H70 should be placed with cool air from outside of the case going through the radiator, so would that mean could I place it at the bottom? The specs on the radiator are:
In normal circumstances the H50/H70 works best drawing air in from the outside, but in the case of the Raven 2 (and Fortress 2, and to a lesser degree Raven 1), the positive airflow design is such that the air flowing over the RAM and CPU area hasn't really been heated up by anything so it's still pretty much as fresh as it was coming in (the GPU area has its own fan flowing over it).
If you really want, there's no harm in mounting the radiator the 180mm fan at the bottom, but I'm not sure what those fans are like for static pressure and also how the mismatch of 180mm fan push with 120mm pull will affect the cooling performance of the H70. You could take out that 180mm fan of course.
Overall though I don't really see much point in worrying - H70 set to exhaust at the top of the case and you're good to go - maybe lose a degree or 2 performance, but if you're pushing your CPU to levels where a degree or 2 makes a difference then you're using the wrong cooler and wrong case.