“We have to ship products, we have to send invoices, we have to collect money,” she said. “HP sells two PCs a second. A server every six seconds. We had to keep selling them.”

The change cannot come fast enough for HP, whose stock is off more than 30 percent since the start of the year. The question is whether Wall Street believes the two companies will benefit from the separation.

“Anytime you make a change, you make a claim,” said Toni Sacconaghi, an analyst with Sanford C. Bernstein. “They say, ‘We’re on the front edge, everyone will have to catch up to us.’ But both new companies aren’t that wildly different. They’re both growth-challenged.”

Of course, quitting history is not simple. HP Inc., the less technically ambitious of the two new companies, will largely occupy the building that used to house HP’s famed research and development division.

The offices of William Hewlett and David Packard, kept intact after they left more than 20 years ago, are being sealed off with a separate entrance so that employees of both companies can come by for visits. The garage and a collection of information technology relics are also common property.

More important for the future of both new companies are the plans that Ms. Whitman seems to have worked on since she took over at HP in 2011. The story HPE is taking to corporate customers is HPE itself.

Need to change your business? HPE can show you how, executives say. After all, few companies in the world have gone to greater lengths to change.