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 QLogic (Nasdaq: QLGC) have plunged today by as much as 16% after the company reported disappointing fourth-quarter earnings.

So what: Revenue added up to $135.1 million, with earnings per share of $0.29. Meanwhile, the Street was looking for $137.6 million in sales with profits of $0.32 per share. The company also booked a big gain on the sale of its InfiniBand business to Intel.

Now what: The $109 million gain related to that transaction was excluded from results related to continuing operations. CEO Simon Biddiscombe said the sale will allow QLogic to focus on higher-growth opportunities like converged networking, among others, while also paving the way for increased investment in its current markets. A handful of firms have now cut price targets and estimates on QLogic, including Needham & Company, Goldman Sachs, and BMO Capital.

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