36 Sun Fire V490 Server Administration Guide • August 2004
About Hardware Jumpers
Three jumpers are located on the Sun Fire V490 system’s PCI riser board. Note that
jumpers are set at the factory to ensure best system performance. Be aware that
moving any jumper shunt from its default location can render the system unstable or
unusable.
All jumpers are marked with identification numbers. For example, the jumpers on
the system PCI riser board are marked J1102, J1103, and J1104. Jumper pins are
located immediately adjacent to the identification number. The default jumper
positions are indicated on the board by a white outline. Pin 1 is marked with
asterisks (*), as shown in
FIGURE 3-5.
FIGURE 3-5 Jumper Identification Guide
PCI Riser Board Jumpers
On the PCI riser board are three jumpers, two of which affect transactions with the
system Boot PROM and one of which is reserved for future use.
FIGURE 3-6 illustrates
the locations of these three jumpers.
Pins
Jumper number
J 2XXX
*
*
*
Asterisks indicate pin 1
Shaded region indicate
s
default jumper position