Dell DX6000 Hardware Owner's Manual page 179

Jumper Setting
NVRAM_CLR
Description
Pins 3 and 5 The configuration settings are retained at
(default) system boot.
Pins 1 and 3 The configuration settings are cleared at
the next system boot. If the configuration
settings become corrupted to the point
where the system will not boot, install the
jumper and boot the system. Remove the
jumper before restoring the configuration
information.
Jumpers and Connectors
179