FORTUNE — It’s only day seven on the job at HP, and CEO Meg Whitman is in a hurry.

Speaking at Fortune’s Most Powerful Women Summit Tuesday in Laguna Niguel, California, Whitman stressed the need for decisive immediate leadership at the company. Citing decades of corporate experience–and her recent failed run for California governor–Whitman said she had a clear sense of what the company needed.

“I’m not in search of the manual,” she explained. “But there’s pacing and sequencing–there are a lot of decisions to be made,” she said. And then there are 320,000 employees, many of whom suffer from a bit of what Whitman calls “a bit of post traumatic stress syndrome.”

First priority: Whitman plans to integrate the UK software-maker Autonomy, for which it paid $10.3 billion. “It closed today,” she said. “We own it and we have to make it work.”

And by the end of October, Whitman says HP (HPQ) will make a decision about whether to sell the company’s PC division. The consequences of delaying the decision would be disastrous, she explained. Then, with an exaggerated nod to the audience, she said, “To any of you in the audience who buy hardware, we are still in the hardware business!”

Full transcript of the Meg Whitman interview

In August, former HP CEO Leo Apotheker announced a strategic shift for the company: The Autonomy acquisition, the end of the HP Touchpad tablet business, and the possible spin-off of its PC business. He was fired just over a month later.

Whitman, who is a supporter of Governor Mitt Romney in his quest to secure the Republican nomination for president, says she sought his advice when weighing her decision to go to HP. He told her to take it. “It’s an opportunity to work for an American icon,” she says he told her. It’s a company that matters greatly to Silicon Valley and to the world.

The former eBay (EBAY) CEO had almost nothing positive to say about the experience of running for governor of California, but she didn’t rule out another run in the future. “I think it would be easier the second time around,” Whitman said. She added that her skin is much thicker now that she’s been through that experience, and any negative press around her decision to join HP has been comparatively easy to handle.

Any second chance at public office will have to be put on hold until Whitman can effectively steer HP in the right direction — a process that could take quite a while. In the meantime, she said she’ll continue to support Romney but that her priority is HP.

Check out our additional coverage from Fortune’s Most Powerful Women summit.

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