The trend of private equity firms buying out high tech companies continues. According to Bloomberg News, Silver Lake Partners and TPG will take Avaya Inc. (NYSE: AV) private for $8.2 billion -- the biggest LBO of a computer networking firm ever.

Investors will receive $17.50 a share. That's 4.7% more than yesterday's closing price and 28% more than before speculation about a purchase surfaced on May 29.

This is the latest in a string of high tech LBOs. Recent ones include:

• Acxiom Corp. (NASDAQ: ACXM), this computer and database services provider, said May 16 it's being bought by Silver Lake and ValueAct Capital Partners LP for about $2.24 billion.
• Alltel Corp. (NYSE: AT) this fifth-biggest U.S. wireless service, agreed May 21 to be bought by TPG and Goldman Sachs Group Inc. (NYSE: GS) for $27.5 billion.
• CDW Corp (NASDAQ: CDWC) agreed on May 30 to be acquired by Madison Dearborn Partners LLC for $7.3 billion.

I am not sold on the competitive advantages that will result from this deal. Maybe there's some overhead to be cut but I question how much private equity is willing to invest in R&D to jump start Avaya's product pipeline.

Peter Cohan is president of Peter S. Cohan & Associates, a management consulting and venture capital firm. He also teaches management at Babson College and edits The Cohan Letter. He has no financial interest in the securities mentioned in this post.

• Rodman & Renshaw downgraded Bioenvision to Market Perform from Outperform, as the firm expects the majority of shareholders to vote in favor of Genzyme Corp.'s (NASDAQ: GENZ) acquisition, but does not believe the transaction price reflects the true value of the company.
• Bioenvision Inc. (NASDAQ: BIVN) was also downgraded at UBS to Neutral from Buy due to the acquisition.
• Archstone-Smith Trust (NYSE: ASN) was downgraded to Hold from Buy at Stifel Nicolaus, to Market Perform from Outperform at Wachovia and to Market Perform from Outperform at Friedman Billings following the acquisition by Tishman Speyer and Lehman Brothers Holdings Inc. (NYSE: LEH).
• GlaxoSmithKline (NYSE: GSK) was downgraded to Sell from Neutral at Merrill Lynch to reflect an unattractive risk/reward profile as they believe Avandia sales will be negatively impacted by the safety concerns raised in the New England Journal of Medicine.

• Clayton Holdings Inc. (NASDAQ: CLAY) was downgraded to Market Outperform from Strong Buy at JMP Securities, as the firm believes a 2H07 recovery in the subprime MBS market is becoming less visible.
• CDW Corp (NASDAQ: CDWC) was downgraded to Peer Perform from Outperform at Bear Stearns following the acquisition by Madison Dearborn Partners.

MAJOR PAPERS:

• The Wall Street Journal reported that CDW Corporation (NASDAQ: CDWC), a $6B market cap technology retailer, is being hotly pursued by a number of private equity firms including Madison Dearborn Partners.
• Avaya Inc (NYSE: AV), a telecommunications equipment maker, is said to be interested in selling all or part of the company, and is in talks with private equity firms and strategically interested companies, the Wall Street Journal also reported.

• Dr. Ronald Krall, the medical director for GlaxoSmithKline plc (NYSE: GSK) told the New York Times that some of the 4,450 patients enrolled in the drug trial for Avandia have dropped out due to safety concerns
• Norsk Hydro ASA (NYSE: NHY) is looking at the possibility of making an offer for Canadian aluminum producer Alcan Inc (NYSE: AL), Globe and Mail reported.
• The Sydney Morning Herald reported that mining company Rio Tinto plc (NYSE: RTP) has hired Deutsche Bank AG (NYSE: DB) to advise it on a possible bid for Alcan.

• According to a report from Chinese-language Commercial Times and noted in DigiTimes, Quanta Computer has reportedly received an order for five million iPhones from Apple Inc (NASDAQ: AAPL) and that the 2nd generation device will offer "a different outer design to fit different markets."