Updated from 2:19 pm with new stock prices

Tech stocks were trading mixed Monday as shares of

Yahoo!

(YHOO)

rose sharply after reports that

Microsoft's

(MSFT) - Get Report

buyout offer for the company could be back on the table.

Yahoo! rose $2.61, or 12.2%, to $23.96 after activist investor Carl Icahn

revived hopes

of a

Microsoft

buyout deal for Yahoo!.

Icahn said he has been in talks for the past week with Microsoft CEO Steve Ballmer, noting Ballmer would be interested in restarting negotiations if shareholders elected Icahn's slate of directors to the board at Yahoo's upcoming shareholder meeting in early August. Yahoo has been under intense pressure from shareholders after it rejected Microsoft's $31 a share offer for the company a few weeks ago.

Shares of

Microsoft

were up 6 cents, or 0.2%, to $26.03.

Data storage company

Network Appliance

(NTAP) - Get Report

gained $1.19, or 5.4%, to $23.13 after Jayson Noland, an analyst with Robert W. Baird, upgraded the stock to outperform from neutral. Noland also raised his price target for the stock to $30 from $24, saying the company has put in place an aggressive growth strategy that includes a strong marketing campaign.

Apple

(AAPL) - Get Report

were up $5.00, or 2.9%, to $175.12 in part because of the anticipation ahead of the release of the 3G iPhone. Apple's 3G iPhone on the

AT&T

(T) - Get Report

network will be available in stores starting Friday.

Chipmaker

Broadcom

(BRCM)

was up $1.88, or 7.2%, to $28.10 in part because of positive research notes from Wall Street analysts. An analyst at Piper Jaffray upgraded the stock to buy from hold, saying investors are underestimating the revenue potential for a few product cycles.

Potential sources of revenue upside include a "key design win" for Nokia's videocore processor, the 3G iPhone for which Broadcom supplies a chip, the migration to high definition video and its impact on Broadcom's sales of set-top boxes and Blu-ray player chips, the analyst said.

A Goldman Sachs analyst also named Broadcom as one of the chip makers most likely to benefit from the strong demand for the 3G iPhone.

Video games maker

Activision

(ATVI) - Get Report

was up $1.12, or 3.6%, to $32.02 ahead of the company's meeting Tuesday where shareholders are scheduled to vote on its merger with

Vivendi Games

.

Activision announced the merger in December and analysts expect shareholders to vote in favor of the deal. Activision also said its game

Guitar Hero: On Tour

for Nintendo DS has sold more than 300,000 copies in the first seven days since its launch in North America.

Shares of

VeriSign

(VRSN) - Get Report

were down $3.49, or 9.5%, to $33.25 after the company said its CEO, William Roper,

resigned

after just a year in the top job. Roper has been replaced by VeriSign founder Jim Bidzos who will now be the Chairman, interim CEO and president of the company.

Nvidia

(NVDA) - Get Report

hit a new 52-week low after it lost 39 cents, or 3.1%, to $12.10. Last week, the company cut its revenue guidance for the second quarter and said gross margin would be lower than previously indicated. Nvidia also took at least $150 million in charges related to defects in certain graphics chips.