194 Power System: Description/Calculating Power Usage
Table 37. Minimum/Maximum Current Rating Configurations
Board Minimum Configuration Maximum Configuration
I/O carrier I/O carrier, I/O riser board I/O carrier, I/O riser board, PCI adapter boards
(10 at maximum load)
Profusion
carrier Profusion carrier, processor mezzanine
board (one), Pentium III Xeon processor
(one), A450NX processor termination
modules (three)
Profusion carrier, processor mezzanine boards
(two), Pentium III Xeon processor
(eight at FMB maximum load), cache
coherency boards (two at 4 Tag configuration)
Memory
carrier (each) Memory carrier, 128 MB DIMM (one) (one
memory carrier only) Memory carrier, 256 MB DIMM (16)
Front panel Front panel Front panel
Midplane Midplane Midplane
Peripheral
bay One diskette drive, one CD-ROM drive,
SCSI backplane One diskette drive, one CD-ROM drive, two
hard disk drives, SCSI backplane
Calculating Power Usage
Use the worksheet in Table 38 to calculate the total DC power used by your server configuration.
The documentation that comes with each add-in device should specify its current and voltage
requirements.
To calculate the total combined wattage for your server:
1. List the current for each board and device in the appropriate voltage level column in the table.
2. Add the currents in each column of the table.
3. Multiply the voltage by the total current to get the total wattage for each voltage level.
4. Add the total wattage for each voltage level to arrive at a total combined power usage on the
power supply.