Document

Integration Guide for New Dual-Core Intel
®
Xeon
®
Processor-Based Servers (or Workstations) Rev 1.0
14
Figure 3.4.1
3.5 SSI Compliant Power Supply
The power supply provides adequate power to the processor, motherboard and other key components. As
shown by research data, most of the server shut-down issues are caused by a power supply failure,
including over-heat protection and over-current protection. So, choosing a reliable power supply is an
important consideration for proper server integration.
Based on the SSI form factor, there are three types of SSI power supplies, EPS1U is used in 1U rack
mount server, EPS2U is used in 2U rack mount server and EPS12V is used in pedestal server. Additional
to that, there are redundant power supplies for 2U and pedestal server, they are ERP2U and ERP12V
respectively.
3.5.1 Mechanical form factors
Below are detailed mechanical dimensions for SSI compliant power supplies:
Form Factor Application Height Width Length
EPS1U 1U rack 40mm 106mm 355mm
EPS2U 2U rack 42.2mm 106mm 348.2mm
ERP2U 2U rack Redundant
83mm 108mm
400mm(Regular)
350mm(Hot Swap)
EPS12V Pedestal 86mm 150mm 140mm (<450W)
180mm (450W~750W)
230mm (>800W)
ERP12V Pedestal Redundant 86mm 150mm 260mm
Table 3.4.3 Power Supply Form Factors
There is no specified requirement on position and length of wire harness of power supply, the base line
is wire harness must make integration and wire plug easier and more beneficial for maintaining.
Some time, the power supply will influence cable layout because of card edge dimensions and small gaps
between the power supply and the chassis, especially in rack mount server where cable layout is
important may impact system thermal performance.
3.5.2 Power level and output rails
Below figure is one typical power budget in one new Dual-Core Intel
®
Xeon
®
based server system. There
are 8 rails recommended in SSI specification for the new platform compliant power supplies, as below:
Figure 3.4.11 System Power Level in 5000 Series Platform