Tech stocks were again flat Tuesday, as analysts were all over the place on a variety of sector stocks. Microchip Technology ( MCHP) was tumbling 10.2%, after guiding below Wall Street's fiscal second-quarter revenue estimates. The company sees net sales of between $258 million and $259 million, below the $267.3 million forecast. The chipmaker sees non-GAAP earnings of 38 cents a share, which beat analysts' 36 cents a share projection, but was below prior guidance. AmTech Research downgraded the stock to neutral from buy. Shares were sliding $3.75 to $32.87. Video game maker Electronic Arts ( ERTS) was edging 1.9% higher after Citigroup initiated coverage of the stock with a buy rating. The bank set a $75 price target. Shares were gaining $1.09 to $59.60. Microchip Technology was the biggest mover on the Nasdaq 100, which also includes component Electronic Arts. The index up 2.18 points at 2165.44. Sprint Nextel ( S) was 2.2% lower after the wireless carrier made a change in leadership. CEO Gary Forsee is stepping down, effective immediately. He is being replaced temporarily by CFO Paul Saleh while a search for his replacement is conducted. Shares fell 40 cents to $18.10. Vonage ( VG) shares dropped 9.7%, reversing gains made Monday, after a Citi Investment Research analyst threw cold water on optimism over its patent infringement settlement with Sprint. The analyst said there was still a 40% chance Vonage goes bankrupt or restructures by 2009, according to the Associated Press. Shares lost 25 cents to $2.32. ValueClick ( VCLK) jumped 9.3%, after RealMoney.com's Jim Cramer stoked the long-running deal rumors for the online advertising company on his "Mad Money" TV show on CNBC Monday night. The stock has been a favorite of buyout speculators since earlier this year, when Google ( GOOG) bought DoubleClick and Microsoft ( MSFT) purchased aQuantive. Cramer said he believed ValueClick could be next. The stock was adding $2.37 to $28.89. United Microelectronics ( UMC) soared 18.7%, after the Taiwanese chipmaker reported a 14.2% jump in net sales in September. The company reported $10.5 million in sales, vs. $9.3 million in September 2006. Shares were rising 68 cents to $4.31. Hoku Scientific ( HOKU) jumped 9.9%, after the solar panel component maker said it had entered into an agreement with Dynamic Engineering, under which it will receive design and engineering services to build a silicon purification unit to make silicon used in Siemens reactors. Hoku shares jumped 89 cents to $9.94. LDK Solar ( LDK) also was on the rise, as the solar panel component maker's shares were rising 8.8% after it upped its third-quarter guidance. The company said it now expected revenue of between $140 million and $150 million, up from its earlier forecast of $115 million to $125 million. Analysts polled by Thomson Financial are expecting revenue of $127.1 million. The company also refuted allegations by a former employee, saying there were no material inconsistencies in its financial statements regarding inventory reporting. Shares were rising $3.30 to $40.80.