NEW YORK ( TheStreet) -- Dell ( DELL) shares climbed 5.78% to $13 in premarket trading on Tuesday as buyout speculation again swirled around the beleaguered tech giant. Bloomberg reported on Monday that the No. 3 PC maker, once the world's largest, is in buyout talks with private-equity firms. Dell hasn't yet responded to TheStreet's request for comment on this story, although the company's shares surged on the media report, closing up 12.96% on Monday. The Texan firm was also the most active premarket Nasdaq stock on Tuesday on share volume of 1,158,531. Facebook ( FB), which hosts a major press event at its headquarters in Menlo Park, Calif., on Tuesday, was another gainer in premarket trading. Shares of the social networker rose 1.14% to $31.30 before market open on Tuesday, after closing down 2.44% on Monday. Facebook was also one of the most active premarket Nasdaq stocks on share volume of 296,165. There has been plenty of speculation about Facebook's likely announcement, with rumors swirling around possible search engine news or a streaming video deal with Netflix ( NFLX). Netflix shares slipped 0.11% to $103.33 on Tuesday after gaining 2.13% during the prior day's session. Shares of key Facebook partner Zynga ( ZNGA) gained 0.38% to $2.63 after rising 1.16% on Monday. TheStreet will be attending and live-blogging Facebook's press event from 12:30 p.m. EST on Tuesday: Mellanox ( MLNX) was another gainer on Tuesday, rising 4.81% to $52.94 after UBS upgraded the storage specialist to buy from neutral and raised its price target to $65 from $56. "We believe the risk-reward for Mellanox is compelling," wrote UBS analyst Steven Milunovich, in a note released on Tuesday. " We are above consensus for 2013 and believe the stock downside is limited." QLogic ( QLGC) also jumped in premarket trading on Tuesday after reporting better-than-expected preliminary third-quarter results. The network infrastructure specialist's shares rose 8.74% to $11.07. Apple ( AAPL), which saw its shares lose 3.5% during Monday's trading, crept up 0.39% to $503.7 on Tuesday. ARM ( ARMH), however, was a laggard, falling 4.81% to $40.56 on share volume of 252,187. Handset giant RIM ( RIMM) was a more modest loser, though, slipping 0.74% to $14.84. --Written by James Rogers in New York. Follow @jamesjrogers >To submit a news tip, send an email to: firstname.lastname@example.org.