I am researching a new computer. The CPU will be an i9-11900 or similar, power consumption 65w.

As far as cooling goes, I want to put in a AIO liquid cooler similar to this:

https://www.ple.com.au/Products/643050/Cooler-Master-MasterLiquid-ML120L-RGB-AIO-Liquid-Cooler-V2

Most of the cases I see can fit only a single fan on the back. There are lot of multi-fan options, but the two or three-fan setups have to be mounted on the top or front (I want to keep the top clear for storage and the front will need space for a 5" drive.

I'll have other standard case fans running as well as the CPU cooler.

A single-fan cooler would make life much easier in the case.

I currently have a single-fan CPU cooler on my i5 and it drops the temp by 45°; the i5 rarely goes above 55° even when flat out for an hour or more.

My question therefore is: do I need a dual-fan cooler for the i9 CPU running at 100% during video encoding, or will a single-fan CPU cooler do?

Thanks very much for any inputs.