HP 3000 customers and advocates love the MPE/iX operating system. The software's elegance and integration more than offset the maturity of an environment now in its fourth decade. Getting a licensed copy of MPE/iX, however, involves purchasing hardware.
Back in 1999, after a set of lawsuits, HP set the business rules in its sandbox that hardware and MPE/iX were inseparable. Then-division GM Harry Sterling compared the MPE/iX license to a license plate on a car. Plates are pretty much useless on any other vehicle, we figure. You have to transfer ownership of the whole kit, under HP's auspices, to get a copy of MPE/iX that you don't already own.
HP still operates a License Transfer office, as it were. Now the service costs $400; it was once free, back in the days when HP was still selling the server.
In other markets HP serves, the OS-to-hardware link isn't quite so rigid. The Digital customers that HP acquired in its Compaq merger get a hobbyist's license for OpenVMS if they want it. Digital and Compaq worked that one out before HP got ahold of those two companies. HP sees more of a future in OpenVMS and the Digital customer base, though you rarely hear about them in HP's strategic pronouncements.
As for that hobbyist license for the HP 3000, we've heard little about it since a year ago, when HP's Mike Paivinen addressed the matter at the OpenMPE meeting. Paivinen said it was well down HP's list of action items.
Paivinen also said HP believes the cost of the forthcoming MPE emulator license — estimated at about $500 in a 2003 HP statement — would be cheap enough to serve for hobbyists. On the other hand, without an emulator, this license isn't going to be available from HP.
So purchasing an MPE/iX license to go along with a generic PA-RISC server you've found on the used marketplace means that server is going to need to have MPE/iX on it already. If you're thinking eBay, you might want to check on how complete the ownership documentation is on the 3000 you're buying. Unless having MPE/iX licensed doesn't matter to you or your company, prepare to pass through the HP License Transfer process to get a "generic box" running an HP-blessed version of MPE/iX