600-2708 PCI Express Expansion System User’s Manual
3-1
Revision 1.0, June 2010
CHAPTER 3
EXPANSION CHASSIS
3.1
600-2708 CHASSIS
The PCIe-451 Expansion Backplane is installed into a seven slot rack mountable chassis. The chassis
provides access to seven of the eight PCI Express slots. All slots can accommodate standard height and
full length PCI Express add-in cards. The chassis also contains three drive bays that may be used to
install peripheral devices for specific applications. There are several four pin peripheral power
connectors, floppy drive connectors and SerialATA connectors available from the power supply.
3.2
SEATING OF CARDS
Unlike standard PC applications, the 2708 Expansion System has a narrow lower gate that precisely
engages the lower end of the PCI Express Add-In board’s face panel. The purpose is to ensure correct
electrical connector mating of up-plugged boards. Failure to accurately mate the lower end of the face
panel with the chassis lower gate will lead to the board not being recognized by the host.
All eight slots of the PCIe-451 have x4 connectors. There is only a x1 lane connection from each slot to
the switch.
3.3
CHASSIS COOLING
Airflow in the 600-2708 chassis is provided by one 120 CFM fan located at the front of the chassis and
two 59 CFM fans located at the rear of the chassis.
3.4
CHASSIS POWER
The chassis contains a 680W ATX12V power supply with two independent 12V outputs, however only
+12-V1 is used by the PCIe-451. The PCIe-451 can support 25W of +12V power at all eight slots.
Assuming the cards also draw the maximum 10W from +3.3V, then a fully populated chassis would
have about 370W surplus power available for peripheral components. .
3.5
POWER CONSIDERATIONS
Table 3-1 through 3-3 show the power consumption for the Cyclone Microsystems boards and the
power supplied to PCI Express slots. Note that the PCIe-425 is installed in and powered by the host
supply. Consequently, the PCIe-425 should not be included as a component of the Expansion Chassis
power budget.
