You probably already know which hardware platform you will use for ColdFusion: the hardware you already own. But if you’re still deciding, keep the following points in mind:
Virtually all ColdFusion code will execute perfectly across all supported platforms. So if you jump ship to another platform during or after development, your applications will require little, if any, porting.
From a ColdFusion perspective, there is no real difference between hardware platforms. The decision as to which platform to use should be driven by cost, experience, support, and other factors.