Figure 17. The c3000 enclosure fan bay and device bay population guidelines  
 
 
Thermal Logic for the server blade 
Precise ducting on HP server blades manages airflow and temperature based on the unique thermal 
requirements of all the critical components. The airflow is tightly ducted to ensure that no air bypasses 
the server blade and to obtain the most thermal work from the least amount of airflow. This concept 
allows much more flexibility in heat sink design. The heat sink design closely matches the server blade 
and processor architecture requirements. For example, in the HP BladeSystem BL460c server blade 
using Intel® Xeon® processors, HP was able to use a smaller, high-efficiency processor heat sink than 
in rack-mount servers. These heat sinks have vapor chamber bases, thinner fins, and tighter fin pitch 
than previous designs. This creates the largest possible heat transfer surface in the smallest possible 
package (Figure 18). The smaller heat sink allows more space on the server blades for full-size DIMM 
sockets and hot-plug hard drives.
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