The reports, by The Wall Street Journal, CNBC and others, indicate that private equity firm Silver Lake Partners is attempting to take Dell private. The unnamed sources in the reports say that Dell, the world's third-largest PC maker, has been in discussion with possible equity partners, and that Microsoft might participate as an investor. Both Microsoft and Dell have declined to comment on the reports.

Reuters is reporting that Dell has created a special committee to analyze any possible deal which, if enacted, would be one of the largest buyouts on record. Microsoft's investment could be "mezzanine financing," a combination of debt and equity. Dell currently has a market valuation of about $23 billion, so a $3 billion investment could give Microsoft a 13 percent stake. CEO/founder Michael Dell owns about 16 percent.

Silver Lake Partners

Last year, Silver Lake Partners worked with Microsoft as a potential partner in an unsuccessful effort to buy Yahoo. In 2011, Microsoft bought Skype from Silver Lake for $8.5 billion, the largest purchase Microsoft has yet made.

If Microsoft did participate in a successful buyout, it would amplify the move it made into computer hardware with the Surface tablet . But such a development doesn't necessarily mean the Redmond, Washington-based technology giant would use Dell to directly manufacture only Microsoft-labeled computers.

Last spring Microsoft invested more than $300 million in Barnes & Noble for its Nook business, plus it made a $180 million commitment over three years in guaranteed revenue-sharing payments for sales resulting from e-books, and a $125 million commitment over five years to back international development of the bookseller's e-book business.

Windows 8, e-Readers

Those investments resulted in that bookseller's commitment to release an e-reader app for Windows 8 and Windows Phone devices. The Nook is an Android -based device, like Amazon's Kindle line, but the agreement also reportedly left open the possibility of Barnes & Noble or Microsoft making Windows-based e-reader devices that participate in the bookseller's ecosystem.

Another benefit: it soothed the legal battles between the two companies, as Microsoft had sued Barnes & Noble for patent infringement. That litigation is now settled, with Barnes & Noble owning a royalty-bearing license to Microsoft's patents.

With a significant stake in Dell, Microsoft could pressure it to put more emphasis on Windows 8 and Windows RT devices, which have had lackluster sales. Microsoft could also head off Dell's potential abandonment of the Windows platform for tablets, a distinct possibility if sales do not improve. Like other manufacturers, Dell could easily concentrate on the Android platform for tablets, which are getting some traction in the market, unless Microsoft intervened.

If Microsoft did invest in Dell and take an even more active hand in its product direction, the equivalent might be Google's purchase of Motorola Mobility, which similarly gave it a hardware partner to further its mobile vision for Android.