Specifications

QSSC-S4R Technical Product Specification System Overview
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protection circuitry for one of the outputs and a FRU EEPROM. It also routes PMBus I2C signals from the power supply
modules to the system baseboard and vice versa. Refer to Section 13 “Power Distribution Board (PDB)” for a detailed
description of the PDB.
9.4 Cooling Subsystem
The QSSC-S4R system contains two cooling fan zones comprising a total of eight system fans located at the upper
front of the system and two dual-motor fans located within each power supply module. The basic chassis structure is
divided into a lower section of 1U height and upper section of 3U height. The upper section is cooled with up to eight
80mm fans positioned in front of the system exhausting into the memory, CPU, and PCIe regions. The lower section is
cooled by fans located within the PSUs drawing air through the hard drives and across the power distribution board.
The zones are designed to be redundant in order to maintain system cooling in the event of fan failure. To maintain
system performance, only one of the eight fans can fail at any one time.
Note: The cooling system is non redundant in a non-redundant power supply system configuration. Each fan assembly has a single
LED to indicate its status. In the event of a fan failure, the LED will illuminate amber. Failed system fans can be hot-swapped out
inside of the chassis with the cover removed. The maximum time limit to perform a fan hot-swap operation is two minutes before
impacting system performance (TBC).
For systems not configured with four processors and eight memory boards, the processor heat sink and memory board
fillers must be installed to maintain proper cooling.
The system thermal design must satisfy individual component specifications with an operating ambient between 0° -
55°C delivered to board. This may result in internal local ambient temperatures greater than 55°C. It is not required that
the maximum internal temperature maintain less than 55°C in all locations.
The ambient air temperature inside the chassis may exceed 55°C in certain locations such as directly behind the
Boxboro chipset, in close proximity to VR components, at the exhaust of the PCI cards. This is not a violation of the
board specification and is normal and expected in those locations. The final success metric for the thermal design is
that all individual components satisfy their respective junction temperature specifications to 99.9% confidence.
The maximum allowable board temperature is 120°C. It is also important to acknowledge the 120°C board specification
when selecting capacitors and other supporting components. Make sure to select components with temperature ratings
that are sufficiently high to withstand being attached to the board which may be up to 120°C in certain locations. A
good rule of thumb is that when those components are placed near (but not limited to) VR’s, Chipsets, Sockets and
other areas where high power dissipating or high temperature rated devices are located, to select a temperature rating
of at least 125°C such that the de-rated reliability temperature is approximately 105°C with a maximum temperature
rating of 125°C.
9.5 Specifications
9.5.1 Environmental Specifications
The production system will be tested to the environmental specifications as indicated in the table below .
Table 30. Environmental Specifications Summary
Environment Specification
Temperature operating 10°C to 35°C (50°F to 95°F)
Temperature non-operating -40°C to 70°C (-40°F to 158°F)
Altitude ASHRAE Class 2, 0 – up to 3,000 m (9842.5 ft)
Humidity non-operating 95%, non-condensing at temperatures of 25°C (77°F) to 30°C (86°F)
Vibration non-operating 2.2 Grms, 10 minutes per axis on each of the three axes
Shock operating Half-sine 2 G, 11 ms pulse, 100 pulses in each direction, on each of the
three axes
Shock non-operating Trapezoidal, 25 G, two drops on each of six faces
V : 175 inches/sec on bottom face drop, 90 inches/sec on other 5 faces
Safety UL 60950, EN60950 and 73/23/EEC, IEC 60950, GOST-R
Emissions Certified to FCC Class A; tested to CISPR 22 Class A, EN 55022 Class A
and 89/336/EEC, VCCI Class A, AS/NZS Class A, ICES-003 Class A,
GOST-R, BSMI CNS13438