• Dell Inc. (NASDAQ: DELL) was upgraded to Buy from Hold at AG Edwards to reflect the strong April quarter results.
• Boyd Gaming Corp. (NYSE: BYD) was upgraded to Outperform from Market Perform at Wachovia due to ongoing improvement in the locals business through revenue growth and cost reductions, expected benefits at Borgata from the summer season, and a new hotel tower at the property.
• OmniVision Technologies Inc. (NASDAQ: OVTI) was upgraded to Buy from Hold at American Technology and to Buy from Neutral at Merriman to reflect the company's improved revenue and gross margin outlook.

• Universal Compression Partners (NASDAQ: UCLP) was upgraded to Buy from Hold at AG Edwards, as the firm believes the potential for additional asset acquisitions creates likely upside to estimates.
• UBS upgraded shares of Norsk Hydro (NYSE: NHY) to Buy from Neutral and shares of Lear (LEA) to Neutral from Reduce.
• Cowen upgraded VistaCare Inc. (NASDAQ: VSTA) to Outperform from Neutral and added shares to the firm's Focus List. Cowen believes the company's decision to review strategic alternatives will unlock value.
• Matrix USA upgraded shares of Whole Foods Market Inc. (NASDAQ: WFMI) to Sell from Strong Sell based on valuation.
• CHLM upgraded shares of 3D Systems Corp. (NASDAQ: TDSC) to Accumulate from Neutral.
• Cantor upgraded shares of NMS Communications Corp. (NASDAQ: NMSS) to Buy from Hold on potential restructuring benefits.

Analysts upgrades 6-1-07: Dell, WFMI, Boyd Gaming originally appeared on BloggingStocks on Fri, 01 Jun 2007 11:11:00 EST. Please see our terms for use of feeds.