NEC HX4500 manual System Power, Software Locks via the Bios Setup

System Power

The system may be configured with up to three 420 Watt power supplies. Each supply automatically switches between these input voltage ranges:

100-120 VAC at 50/60 Hz; 7 A maximum current

200-240 VAC at 50/60 Hz; 3.5 A maximum current

Each power supply provides DC outputs of +5 V, +12 V, +3.3 V, -5 V, and -12 V. All output grounds connect to the power supply chassis and to earth ground through the AC line cord. Each supply has:

individual AC input line cord that plugs into the external side of the power supply

isolating device on each DC output so that the failure of one supply does

Tnot affect the operation of the others

cooling fan integral with each power supply enclosure. The fan circuit implements fan failure detection.

In a system, power is drawn equally from all supplies installed. A system with two power supplies can be fully loaded (all drive bays and add-in board slots filled). The supplies use a forced current-sharing technique that ensures the supplies share within 10 percent at full load. In a high-access system with three power supplies, the third supply gives redundancy, because the load is redistributed if one supply fails.

Software Locks via the BIOS Setup

The BIOS Setup has software features that let you control access to one or more parts of the system:

set and enable an administrative password

set and enable a user password

Tenable password on boot

disable writing to the diskette drive when secure mode is set.

If only a supervisor password is set and enabled, enter this password to boot the server and run the SCU.

If both the user and administrative passwords are set and enabled, enter either one to boot the server. Enter the administrative password to access the SCU or BIOS Setup to change the system configuration.

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