Case fan Depth - basic question

CW Fox

Honorable
Jun 19, 2013
1
0
10,510
This probably sound a bit dim, but is it right that 15mm case fans will not be as efficient as 25mm deep case fans? I've just ordered a new fan because the old one has gone very noisy and I was paying so much attention to getting the same ampage (0.18A and 80mm) as the existing one that I didn't notice it was a 15 rather than the 25 I currently have installed. Is this going to make a difference worth worrying about? Do I need to look again?

Thanks.