The view of Silicon Valley’s top venture capitalists on the downturn: act responsibly, but don’t panic.

That’s one of the messages at the first panel Wednesday at conference on “How to manage your start-up in the downturn.” The conference, at the Stanford Park Hotel in Menlo Park, has a full house of a couple of hundred people.

Matt Marshall, editor and chief executive of VentureBeat, started the panel with a question about what the panelists thought about the “Good Times R.I.P.” presentation by Sequoia Capital, which recommended that start-ups slash spending. John Doerr said that it was good advice because the downturn was so serious. Doerr, a partner at Kleiner Perkins Caufield & Byers, said that 40 percent of the world’s market value (which he said was $165 trillion) has evaporated. Ram Shriram, an early investor in Google, said that this business cycle is affecting both businesses, which are slashing information technology funding, and consumers, who have been hit by the credit crunch.

Matt Cohler, a former executive at Facebook and now a partner at Benchmark Capital, said that he hadn’t heard many people talk about the fact that start-ups shouldn’t panic now. However, one of the first things the panelists did was talk about just how bad and unprecedented the downturn is.

Ron Conway, one of Silicon Valley’s most prolific seed stage investors, said that the best place to get cash now is from existing investors. He recommended companies that have less than a year of cash go to their investors and ask for a bridge loan. That way, they can find out immediately if their existing investors will be able to support them or not. Then the start-ups can plan accordingly.

Conway had a lot of perspective from the last downturn, where he was highly exposed to the 2000-2001 crash. Last time, he had 224 companies in his portfolio. Of those, 70 percent, or 164 companies, went out of business. His team had to go into triage: those companies with less than a year of cash had to be shut down. The rest could receive more money than previously anticipated. Now, Conway says he has invested in 130 companies since 2005. Only 13 percent of those companies have less than a year of cash. He has gone to those companies to confront them with the problem.

He noted that this downturn is different because the epicenter isn’t in Silicon Valley. It will certainly be hit by the ripples of the downturn from other quarters, but he noted he would continue to invest. The winners from his portfolio last time were Google, PayPal, and Ask Jeeves.

Shriram said that overseas markets won’t be a panacea for investment money. Countries such as India are still hampered by infrastructure problems and thus don’t have as many tech start-up investment opportunities. Nothing, he noted, is decoupled from the global market in crisis.

Kittu Kolluri, a partner at New Enterprise Associates, said that India is indeed not ripe for hundreds of millions in investment in start-ups. But there are more opportunities for late stage investments than there were. But he said that companies that target both the Indian and Chinese markets could get off the ground.

“They’re markets that are ripe at this point and could become very big, particularly mobile,” Kolluri said.

Doerr came prepared with a list of the top things that start-up CEOs should do. He surveyed 18 of Kleiner’s companies and came up with the suggestions as follows:

• Act now. Act with speed. Raise money. Get a loan. Focus, cut or sell.

• Protect the vital core of the company. Use a scalpel instead of an ax. Be surgical.

• Make sure you have 18 months of more of cash on a conservative revenue forecast.

• Defer any facility expansions. Don’t spend money on tech infrastructure, such as new software or computers, if you don’t need it. He noted that Andy Bechtolsheim told him that Arista (new start-up) is getting by on Google Docs (free software instead of Microsoft Office.) Reevaluate your R&D priorities.

• Renegotiate any contracts that you can. Everything is negotiable.

• Everyone in the organization should be selling, from the receptionist to the engineers.

• Offer people equity instead of cash as bonuses. (You can do this with outside vendors as well).

• Pay atention to where your cash is. Treasuries, for instance, are more secure than money market funds.

• For your revenue plan, pay attention to leading indicators.

• Over-communicate with everyone: employees, investors, key customers. Let them know your resolve and don’t sugar coat things.