Critics of the buyout say it's a textbook example of how technology markets can flip-flop overnight. The buyout group "put a little too much faith in how much Motorola's market share would go up," says Ping Zhao, senior analysts at CreditSights, a debt research firm.

In the meantime, Motorola is diversifying its supply chain away from Freescale in favor of chips from Texas Instruments and Qualcomm. "The company won't go bankrupt," says Zhao. "But its business will not recover anytime soon."

First Data is another deal worth watching. It's considered a great company, but KKR paid an extremely high price for it—on average, buyout deals until late last year were priced at 8.6 times earnings before interest, depreciation, taxes, and amortization.

The Freescale deal was considered expensive at 11 times. KKR paid 15 times for First Data, an extraordinary premium, and with a debt load considered heavy even for a private equity buyout. Any hiccup in First Data's business could beat down KKRs expected returns in a hurry.

Freescale's problems may have helped push KKR to beef up its tech talent. In June, it hired two key senior advisers: Heinz-Joachim Neubürger, former chief financial officer at Siemens, and Richard Klemmer, recently chief executive at Lucent spinoff Agere Systems, a semiconductor company acquired in April by LSI Corp.

A couple months earlier, KKR had put partner Michael Marks, former boss at Flextronics, the giant international manufacturing contractor, on the board at Sun Microsystems. KKR earlier this year invested about $700 million in convertible bonds at Sun.

"People go on boards to gain influence" in Silicon Valley, says Terry Garnett of technology-focused private equity firm Garnett & Helfrich. "John Doerr was on the board at Sun for many years; Don Valentine on the board at Cisco."

If tech buyouts were easy, however, the debt-starved balance sheets would have attracted huge waves of buyouts a long time ago. Technology is a lot more complicated than, say, hotels or radio stations or women's hosiery.

Success or failure at Freescale, First Data, NXP Semiconductors, Avaya, and others will determine how far and fast private equity spreads through the tech sector.