Sun Microsystems Fire V890 Service Manual page 247

The following illustration shows the four CPU/Memory board slots on the system
motherboard. The slots are labeled A through D from bottom to top. The virtual
processors (CPUs) in the system have unique numbers, depending on the slot where
each CPU/Memory board resides. For example, a CPU/Memory board installed in
slot D always contains CPUs 5 and 21 and 7 and 23, even if there are no other
CPU/Memory boards installed in the system.
7, 23
5, 21
Slot D
6, 22
4, 20
Slot C
3, 19
1, 17
Slot B
2, 18
0, 16
Slot A
Chapter 7 Hardware Configuration 219