As far as Cooling for the CPU, There would be somewhat of a problem to consider with additional Noise/Power Usage (Three refrigeration units running instead of the current Two), Although it hasn't Stopped me as of Yet from attempting to improve on my Testing/Benching Sessions every chance I get.
My Main Focus lately is towards finding better Cooling on the Graphics Cards using solutions that will work with Minimal Operating Maintenance in a 24/7 System, Since they definitely impact the Various Benchmark Scores based on High GPU/Memory Overclocks.
For Example,........ I was thinking (daydreaming) about running just a Single KPE using my Vapochill XE for sub-zero cooling and probably would get a Much Higher 1X GPU OC/Benchmark Score than on just chilled water cooling.
The Funny thing about that situation is I also happen to have Three More Vapochill XE's laying around, But I would have to find a different way to attach the Vapo head to the GPU if I wanted to cool more than One Graphics Card.
Call me Crazy, But I've even been considering PCIe RISERS for clearance purposes and I'm sure you could picture in your Mind what THAT System would look like!