Compaq AlphaServer DS10 Reference Manual page 19

Memory size is determined.
The PCI bridges and attendant buses (indicated as IODn by the console)
are probed and the devices are reported. I/O adapters are configured.
Power-up slot 14 corresponds to the bottom physical slot, slot 0. See Figure
1–3.
Slot Location Physical Slot Number
Top
Second from top
Second from bottom
Bottom
These devices are behind bridge of the card in logical slot 15, physical slot
1, second from the bottom.
This device in is logical slot 16, physical slot 3.
Logical slot 17 is physical slot 4, the top slot.
The SRM console banner and prompt (>>>) are printed.
The SRM console is a command-line interface you use to set or read system
parameters.
If the auto_action environment variable is set to boot or restart and the
os_type environment variable is set to unix or openvms, the Tru64 UNIX
or OpenVMS operating system boots.
If the system is running the Windows NT operating system (the os_type
environment variable is set to nt), the SRM console loads and starts the
AlphaBIOS console.
See Section 2.19 for information on environment variables. See Chapter 2
for SRM console, and Chapter 3 for AlphaBIOS information.
Logical Slot Number
3
2
1
0
Operations 1-5
17
16
15
14