Intel (INTC 0.64%) has been maligned for missing the mobile revolution. However, if you stop and think about it, Intel's PC business is larger than the entire mobile system-on-chip market.

This can be verified with some pretty simple math. According to Intel, the mobile applications-processor market comes in at about 1.5 billion units. Assuming a $20 average selling price for these chips, it stands to reason that the entire mobile chip market comes in at about $30 billion, give or take a few billion. Intel's PC chip business will be about $33 billion in 2013.

Mobile or not, Intel's fortunes depend on the PC
Step back and really absorb the magnitude of this fact: Some $33 billion of Intel's roughly $53 billion yearly revenue comes from PCs. Further, this business had a very nice operating margin of around 35% during 2013, even amid excess capacity charges taken early in the year. Investors should make no mistake -- the company is dependent on the PC market in a big way.

Now that the company is finally making meaningful inroads in mobile, this will be a very nice incremental opportunity. Indeed, if the company is able to take 20%-30% of the mobile apps processor market, then that's a cool $6 billion-$8 billion in incremental revenues. But it won't compensate for a PC market that continues to crater.

It's a double-edged sword
If the PC market continues to crumble, it would take sheer dominance of the mobile market to compensate for that decline -- only the data-center group's growth could even have a chance of driving Intel back to revenue growth. However, if the PC market rebounds, the game really changes. Mobile goes from a save-the-company initiative to an incremental growth opportunity.

Is the tide turning?
According to Digitimes, chip manufacturer Taiwan Semiconductor (TSM -0.34%), or TSMC, has apparently begun to see an uptick in orders from PC-levered names such as AMD (AMD -0.35%) and NVIDIA. (Intel builds its chips at its own manufacturing plants). While this is mildly positive for TSMC, which is also levered to the fast-growing mobile markets, it could end up being very positive for Intel and the PC-levered names in general.

As far as Intel is concerned, it has been taking share in PCs over the last couple of years, so an uptick in sales over at AMD probably is more of a secular signal than a structural improvement in AMD's market-share position. This is bullish for the PC market as a whole and, by extension, Intel. This is also probably why Intel's shares are near a 52-week high.

Looking ahead to 2014
It's too soon to tell whether this alleged uptick in PC demand is a long-term phenomenon or a proverbial flash in the pan, but there is now legitimate hope that Intel may be able to exceed the guidance that it gave at its analyst day of a mid-single-digit PC revenue decline, coupled with flat operating profit.

Foolish bottom line
While management gave uninspiring guidance at its analyst day, nobody really has a handle on what the PC market will do in 2014. The trends seem to suggest that emerging markets are still very volatile due to tablet growth, but that mature markets are stabilizing. Only time will tell how it all plays out.

One thing is for sure: If the PC market surprises to the upside, Intel, as well as other PC-levered names, could outperform after several years of struggles. And that, in this highly frothy market, could be where the opportunities lie.