NonStop S-Series Server Description Manual (G06.24+)
Introduction
HP NonStop S-Series Server Description Manual—520331-003
1-2
Processor Enclosures and I/O Enclosures
Processor Enclosures and I/O Enclosures
A NonStop S-series server is a computer system that is structured around many 
parallel components, both physical and logical. For example, a single server can 
include up to 16 processors (CPUs).
Processors are housed two in a processor enclosure. Thus a four-processor server 
would be contained in two processor enclosures, as illustrated in the left part of 
Figure 1-1. As will be shown later, processor enclosures include a considerable I/O 
capability, so that I/O enclosures, illustrated as part of the server in the right part of 
Figure 1-1 would only be needed where I/O requirements exceed the I/O capability 
built into the processor enclosures.
Processor enclosures and I/O enclosures are structurally the same. A processor 
enclosure can be converted to an I/O enclosure (or vice versa). Primarily, the 
conversion requires swapping the internal processor multifunction (PMF) CRUs for 
I/O multifunction (IOMF) CRUs. (CRU is customer-replaceable unit.) 
The processor enclosures for NonStop S7000 servers differ from other processor 
enclosures in one major way. At the bottom of the other enclosures, a shelf houses the 
power supplies for the processor multifunction (PMF) CRUs. This space is empty for 
the NonStop S7000 server. The reason for this difference is that the power supplies for 
the NonStop S7000 processors are part of the processor CRU but are separate for the 
other processors.










