Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of radio-chip designer RDA Microelectronics (Nasdaq: RDA) are at it again, jumping sky-high for the third time in the last three weeks. It's up more than 13% on about three times the average daily trading volume.

So what: The last two pops had little to do with solid news, but things are different this time. Credit Suisse just started covering RDA with a "buy" rating and a 17% price target.

Now what: Feel free to take that positive rating with a shovelful of salt, though: Credit Suisse just happens to be one of the underwriters who stand to benefit handsomely from its overallotment positions in the company. Chinese semiconductors may be a hot ticket, like anything else related to the Middle Kingdom, but you'd still do best to approach this stock with extreme caution -- it might bite!

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