The Aquaero has 4 fan channels and you will be able to control as many fans as you can without exceeding the each channels output and the overall Aquaero output (more than 1 fan on each channel). Each fan channel can deliver 1.65A and the maximum combined of all channels is 5A. I'm not sure what fans you are trying to use, but depending on which will determine if you can or cannot. I'm going to go out on a limb and say that 10 fans will most likely exceed the output. You will need a PowerAdjust2.
For example 3 Scythe Ultra Kaze 3000's utilize 1.8a at normal speed. You will only be able to run 2 Ultra Kaze's (1.2a) on a single channel. You may be able to run 8 Ultra Kaze's (2 per channel), but you would be approaching the XT's thermal limits.
Also, since you want to control two PMP-450's you will definitely need a PowerAdjust2.
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