If investors are planning on selling in May, they showed no signs of it today, with stocks posting strong gains on the second-to-last day of April. The Dow Jones Industrials (DJINDICES:^DJI) finished up 106 points, less than 50 points away from a record high, while the S&P 500 finished at a record by less than a quarter of a point.

Looking at the three top gainers in the Dow, you'll find a who's-who of the technology industry filling all three slots. Hewlett-Packard (NYSE:HPQ) led the way higher with a 2.65% gain, pushing the stock above the $20 mark. Fool contributor Anders Bylund earlier today attributed the gains to speculation that activist investor Carl Icahn could build a position in HP, although one wonders just how many projects Icahn can take on without overextending himself. Worth considering is that despite the idea that the PC market is in decline, HP is nevertheless the top-volume seller of PCs in the world, and despite the company's attempts to diversify beyond personal computers, the segment will continue to drive HP's overall results for years to come.

Microsoft (NASDAQ:MSFT) finished up 2.6% as investors continue to ride the momentum that has sent the stock up double-digit percentages in just a handful of trading sessions. With Microsoft presenting at a Paris conference this week, new products could be one reason for the gain, but for longer-term investors, Microsoft has lagged behind many of its tech peers for more than a decade now. Any hint that the company can regain its past success could lead to an immense move for the shares, of which we may only have seen the beginning.

Finishing the Dow tech trifecta is IBM (NYSE:IBM), which picked up 2.5%. The company presented some new Big-Data-related software and services at its IMPACT 2013 conference in Las Vegas. With the goal of integrating technological resources to improve the experience that customers have with businesses and to help companies build competitive advantages in their respective industries, IBM hopes that its MessageSight appliance can help collect and use data from billions of mobile devices and other data sources.

Finally, outside the Dow, SunPower (NASDAQ:SPWR) hit a 52-week high, rising 3% in follow-through on last Friday's upgrade and news that it had started construction of its California-based solar project with MidAmerican Solar. As the largest solar development under construction, the project not only will provide power to 400,000 homes but also represents a key step forward for an industry that has struggled under overcapacity and concerns about falling subsidies.

Fool contributor Dan Caplinger has no position in any stocks mentioned. You can follow him on Twitter: @DanCaplinger. The Motley Fool owns shares of IBM and 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.