Apple Mac Pro - Power Supply and Environment

106 Chapter 5 What’s Under the Hood
Â Total harmonic distortion + noise: Lessthan-60dB(0.1percent)
Â Frequency response: 100Hzto8.2kHz,+0.5dB/-3dB
Power Supply
AC line input
Â Voltage ranges: 100–240Valternatingcurrent(AC)
Â Current: Maximumof12A(lowvoltagerange)or5A(highvoltagerange)
Â Frequency: 50–60Hzsinglephase
Power Requirements for Expansion Cards and Peripherals
Expansion cards
CombinedmaximumpowerconsumptionforallfourPCIExpressslotsshouldnot
exceed300watts(W).
USB devices
Eachofthecomputer’sbuilt-inUSBportsisallotted500mA.
FireWire devices
Thecomputercanprovideupto28WtotaltotheFireWireports.
System Clock and Battery
YourcomputerhasCMOScustomcircuitrywithalong-lifebattery.
Battery
Usea3-volt,BR2032lithiumcoincellreplacementbattery(see“ReplacingtheInternal
BackupBattery”onpage73).