In tip 0515, I detailed the available switches in boot.ini. In tip 2319, I described the Safe Boot switches, for Windows 2000.

Windows 2000 Advanced Server and Windows 2000 Datacenter Server support the following additional switches:

/PAE      - Enables support for 8 GB of memory for Windows 2000 Advanced Server
                   and for 32 GB of memory for Windows 2000 Datacenter Server.

/NOLOWMEM - Loads the entire system (drivers, pools, programs, etc.) above 4 GB.