While Fools should generally take the opinion of Wall Street with a grain of salt, it's not a bad idea to take a closer look at particularly stock-shaking analyst upgrades and downgrades -- just in case their reasoning behind the call makes sense.

What: Shares of Lam Research (LRCX 0.33%) gained 1% this morning after Piper Jaffray assumed coverage on the chip equipment technologist with an overweight rating.

So what: Along with the bullish call, analyst Ruben Roy boosted his price target to $80 (from $62), representing about 15% worth of upside to yesterday's close. So while contrarian traders might be turned off by Lam's year-to-date price strength, Roy's call could reflect a sense on Wall Street that industry tailwinds give the stock plenty of room to run.

Now what: According to Piper, Lam's risk/reward trade-off is rather attractive at this point. "RCX's analyst day highlighted growing semi industry trends which will drive ongoing WFE growth and an estimated $2b addressable market expansion for LRCX," said Roy. "We believe that LRCX is positioning itself well to capitalize in industry inflections in mobility and IoT, allowing it to remain in a leading industry position which increasingly requires greater technological precision at advanced semiconductor nodes." With Lam shares now up more than 50% from their 52-week high and trading at a P/E of 25, however, much of that progress might already be baked into the valuation.