Enough fans to overclock?
I'm building my pc soon and I want to overclock it, I have an Intel Core i5-7600K cooled by the Cryorig H7, an MSI GeForce GTX 1070 Ti Gaming 8G (it has 2 MSI TORX 2.0 fans) and 2 case fans included with the NZXT S340 Elite. I still have enough room for 2 case fans and the Cryorig H7 has extra mounting brackets for another fan. I wanted to know if this is enough to overclock or if I should buy one or more fans extra.
Number of fans is not the determining factor, really.
One, quality intake fan could well exceed the airflow of multiple, lower quality fans (of various configurations), within a case.
At a high level, the H7 in the S340 is sufficient for *some* overclocking. I'd start with what you propose..... and if airflow seems poor/temps are higher than anticipated, you can experiment with either adding more fans, or replacing the stock fans with "better" fans.
From what I've seen, the addition of a secondary fan to the H7 doesn't lower temps dramatically - a couple of degrees at best.