If you think that the Dow Jones Industrial Average (DJINDICES:^DJI) is moving today -- and it is, up a robust 1.3% as of 2 p.m. EST -- just wait until tomorrow.

Hewlett-Packard (NYSE:HPQ), one of the 30 components that make up the popular market gauge, reports its fiscal fourth-quarter results on Tuesday morning.

Investors aren't holding out for much. They saw HP rival Dell (NASDAQ:DELL.DL) disappoint last week, delivering double-digit percentage declines in revenue and profitability. HP's results probably won't be that scary; analysts see revenue and earnings slipping 5% and 3%, respectively.

However, it's safe to say that any significant surprise on either end of the spectrum would move the Dow higher or lower.

It's not just about HP's own impact in the 30-stock index. Fellow Dow components Intel (NASDAQ:INTC) and Microsoft (NASDAQ:MSFT) are also likely to move if HP offers up a surprising report. If it sheds some light on how PCs and laptops have been selling since the rollout of Microsoft's Windows 8, it will really get the Dow moving one way or the other.

Intel has tried to wean itself from the PC market. Its chips and microprocessors can also be found on some tablets and smartphones, but not enough -- for now. Intel is still at the mercy of the PC market, and that's a niche that's been stagnant in recent quarters.

Microsoft naturally has a lot riding on HP's report. HP is the world's largest maker of PCs, and most of its machines run Microsoft's operating system.

HP's perspective on the near term will probably be a bigger factor in moving all three of these Dow components than its quarter that ended in October.

One way or another, the Dow will probably move on Tuesday because of HP.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.