Should I get a laptop cooler that brings in cold air or pushes out hot air?

[smashmouth900]

I want to get some sort of cooling for my laptop, but should I get a cooler that Blows Cold Air In or Sucks Hot Air Out. I just wanted to know which is best for decent cooling. Thanks in advance.

 

[Traditore]

If laptop's cooler blows out hot air just fine, you should get something that will blow cold air in through laptop's intake holes.