There were room-sized mainframes, costing hundreds of thousands of dollars, that were built one at a time by companies such as IBM and CDC.
Last year, HP started giving away expensive hardware (in some cases mainframes costing tens or hundreds of thousands of dollars) in exchange for an undisclosed percentage of revenue taken in by the customer.
In the early days of computing, companies either had to buy a mainframe, which cost millions, or share one with someone else.
Multiprocessor systems first appeared in large computers known as mainframes, before their costs declined enough to warrant inclusion in personal computers (PCs).
But when support is factored in, Greiner adds, the cost of mainframe ownership "an be equal to or less than"the cost of running Unix systems.
The servers use microprocessor-insulating technology and other features I.B.M. had previously deployed in mainframe computers to cut costs and improve reliability while bolstering processing speed.
At a price of $120,000, the PDP-1 sold for a fraction of the cost of mainframe computers, albeit with vastly more limited capabilities.
The company compensated for weak sales, especially of personal computers and mainframes, through strict cost controls.
I.B.M. asserts that the mainframe is often the lowest-cost technology when running many different programs because fewer people are needed to maintain a mainframe, and it consumes less power, than a cluster of many smaller machines.
In the beginning IBM ruled the world with its giant mainframe computers, hulking beasts that cost a fortune and were a pain to program.
