NEW YORK (CNN/Money) - Credit Suisse First Boston raised its 12-month price target Wednesday for shares of search engine Google to $350 more than 25 percent above current levels.

The move comes the day after Piper Jaffray raised its price target for the stock to $300. CSFB raised its target after Google shares reached its previous near-term price target of $275 Tuesday following the boost by Piper Jaffray.

Google shares, which gained $11.27, or 4 percent, to $277.27 on Tuesday, gained another $6.93, or 2 percent, to $284.20 in pre-market trading on Inet Wednesday. The Tuesday close represents a 226 percent gain for the stock from its $85 initial public offering price last Aug. 19.

"While there will certainly be plenty of volatility in the stock price, particularly over what is supposed to be the slower summer period, we believe shares have further to go given the momentum in the company's core advertising business, the growing impact of new business like Gmail, Froogle, and Local, and a valuation that, relative to the company's growth rate, is far from stretched," said CSFB's note to clients.

"On a relative valuation basis, Google is trading roughly inline with Yahoo! (Research) and at a slight premium to eBay (Research)," said the note.

Google is trading roughly 42 times CSFB's 2006 earnings estimate and 24 times its estimate for Google's earnings before interest, taxes, depreciation and amortization (ebitda). Yahoo! is trading at 55 times CSFB's earnings forecast and 24 times its ebitda forecast, while eBay's price ratios are 37 times earnings and 21 times ebitda.

"We would argue that because of its superior growth rate Google should trade at a premium to both companies," said CSFB's note.

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