The Movers Behind Today's Dow Drop

The markets slowed down a bit today, as light volume and modest declines displayed a cautious attitude on Wall Street. Fearing revived European debt issues, the Dow Jones Industrial Average fell 21 points, or 0.16%, to close at 13,971.

Microsoft led today's blue-chip performers, gaining 1.1% two days after the highest-priced of the company's new Surface Pro tablets sold out within hours of coming out. The 128 GB devices, which retail for $999, were ostensibly so popular that Microsoft grossly underestimated the overwhelming demand. A more cynical observer might posit that maybe there weren't a ton of the 128 GB models to begin with, and Microsoft knew the meager supply wouldn't be enough to meet the slightly less-meager demand.

Meanwhile, Boeing continues to deal with issues from its Dreamliner 787 fiasco, as the company conducted a second round of flight tests measuring the Dreamliner's performance on Monday. Boeing shares fell 0.9% today, as investors heard airplane industry experts such as International Airline Group's CEO Willie Walsh predict that Boeing will need to redesign its battery, in a process that could take "a couple of months." For future reference: Cutting corners doesn't work so well if you're an aerospace company.

Although chipmaker Advanced Micro Devices has lost almost two-thirds of its market cap in the past year, shares have rallied nearly 30% in the past three months alone, shortly after announcing restructuring initiatives in October. Investors have thus far been pleased with AMD's vow to "simplify product development cycles," fund promising opportunities, and "reduce our breakeven point."

Closing out the day, shares in online gaming business Zynga rocketed 7%, continuing the remarkable rally Zynga shareholders have witnessed in the past week. After shocking Wall Street last Tuesday, when the company reported profits, shares took off. Today's impressive gains are run-of-the-mill when taken in context with other daily gains in the past five trading days, which has sent shares 44% higher.

With that in mind, Zynga's post-IPO performance has still, frankly, been dreadful, and investors are even beginning to wonder if it's "game over" for this newly public company. After all, being so closely tied to the world's largest social network can be a blessing and a curse. You can learn everything you need to know about Zynga and whether it's a buy or a sell in our new premium research report. Don't even think about picking up shares before you read what our top analysts have to say about Zynga. Click here to access your copy.

The article The Movers Behind Today's Dow Drop originally appeared on Fool.com.

Fool contributor John Divine has no position in any stocks mentioned. You can follow him on Twitter, @divinebizkid, and on Motley Fool CAPS, @TMFDivine.The Motley Fool owns shares of Microsoft. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.

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