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 (UNKNOWN: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.

Longtime Fool contributor Rick Aristotle Munarriz has no positions in the stocks mentioned above. The Motley Fool owns shares of Intel and Microsoft. Motley Fool newsletter services recommend Dell, Intel, and Microsoft. Try any of our Foolish newsletter services free for 30 days. We Fools may not 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.