NEW YORK ( TheStreet) -- HP ( HPQ) was a big winner before market open on Wednesday, boosted by analyst upgrades. Citi Research, for example, upgraded HP to buy from sell early on Wednesday, citing potential for upside at the embattled tech giant. Catalysts for the stock include an uptick in HP's services business and the financial benefits of the firm's cost-cutting, according to Citi. Shares of HP rose 2.67% to $26.15 before market open. Sirius XM ( SIRI) was also a winner as the Internet radio giant continues its recent momentum. Shares of Sirius climbed 0.7% to $3.62 before market open, after gaining 2.3% during Tuesday's trading. In a statement released early on Tuesday, Sirius announced that it added 715,000 net new subscribers during the second quarter, taking its total subscribers to more than 25 million. Sirius also raised its full-year guidance for total net subscriber additions to 1.5 million, from its previous guidance of 1.4 million. The New York-based firm was also one of Wednesday's most active pre-market Nasdaq stocks on share volume of 432,505. Social gamer Zynga ( ZNGA) was another winner, climbing 2.1% to $3.41, while its partner Facebook ( FB) rose 0.47% to $25.60. Shares of Vodafone ( VOD), however, slipped 1.08% to $28.51 while Micron Technology ( MU) was off 0.95% to $13.01 before market open. --Written by James Rogers in New York. Follow @jamesjrogers >To submit a news tip, send an email to: email@example.com.