Also, I don't mean to sound critical but another issue you are facing is the fact that you are always looking at a single box, which is not flanked/surrounded by other boxes as it would in a typical 5 boxing arrangement. This combined with the 22" size is going to make it hard to box effectively. When your main screen is flanked by 4 screens, it is much, MUCH easier to see a change in your peripheral vision than if you are looking, say at your lower right - especially if you use 15 or 17" monitors.

P.S. - Dispersing the computers is a good idea to avoid hot spots but they will still heat the room just the same. You have to physically either vent all of the air, cool all of the air or physically move your computers out of the room.

I ultimately had to do all three but I wanted to get rid of the noise and I have 12+ computers and a whole bunch of other stuff needing cooling.