During my shopping frenzy, I got the Shuttle KPC K45 from Canada Computers where they built it as a ready-to-go system. Overall I was pretty happy with it, but it had 2 problems: the CPU and hard drive was slightly overheated at 46°C and 45°C, and it was loud; sounding like a hand held vacuum cleaner.
I opened the case and found out that Canada Computers only installed cheap Intel CPU fan that wasn’t PWM controllable. This meant the fan would always run at it’s top speed (approx. 2300 rpm) and was the reason for the loud noise. They also didn’t bother to install case fan. It was pretty obvious I needed to install a new cooling system for my Shuttle, otherwise it might die of overheat.
I went with Arctic Cooling, (good reviews, and low cost). More specifically, I used the AF9225 PWM for the case fan, and Alpine 7 GT for the CPU. The fan for Alpine 7 GT was actually smaller than the Intel stock fan, but it was also the only CPU fan which could fit inside the Shuttle.
With 2 fans installed the system was only making a humming sound compared to the preivous vaccum cleaner as the the CPU and case fan running at 1350 rpm and 800 rpm respectively. Even with the slower rpm the temperatures for the CPU and hard drive still dropped to 42°C, and 36°C. Considering that the cost was only $7.99, and $10.99 for the case and CPU fan, it was a well made investment. 
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