Like for the UNIX/Linux based approach, you need several information and data before setting everything. First of all, you need the MAC address of your PA-RISC box. Please read these instructions. You are going to need a lifimage file. Please read these instructions.
Then, you have to enable DHCP service on your Windows™ 2k box. You can do that by going into the Control Panel then Add/remove programs then Windows components and finally Networking Services. There you will ask for Dynamic Host Configuration Protocol (DHCP).
You need to setup the DHCP service now. Launch the DHCP admin tool by going into the Conttrol Panel, Admin Tools and DHCP.
Expand your server tree.
Right click on Reservations. Select "New Reservation...".
For reservation name, I put my workstation's host name. Enter an unused IP address. Enter the PA-RISC box' mac address (no delimiters, just the hex number). Select "Both" for whether it should be bootp or dhcp. Click "Ok" to close this window.
Find your new reservation at the bottom of the list under Reservations and click it.
Right click "Configure Options..."
It should have inherited your server's default options, so I won't cover setting router, dns, wins and lease length.
Scroll down the list of options to 066 "Boot Server Host Name". Check the box next to option 066. Enter your tftp server's ip address because I don't trust DNS to work in IPL.
Check option 067 "Bootfile Name" and enter the name of the lifimage. Generally, lifimage is a good choice here.
Click "Ok" and your dhcp server is ready !