The earnings warning by graphics chip makerNvidia may be a symptom of bigger things, such as a glut of semiconductors.

A report today by Macquarie analyst Shawn Webster has some pretty stunning numbers:

That there are an estimated 10 to 16 millionexcess processors out there. 

That's roughly 11 to 18 percent of the quarterly processor shipment rate, which above historic norms.

If the trend continues into the fourth quarter, that could translate into dollar volume of $1.1 billion to $1.9 billion in excess inventory.

Here's the rub: PC demand simply may not be enough to sop up all of the extra chips.

Why care? Bloated inventory is never good. Webster believes you would need 24 to 26 percent PC growth to make the extra chips disappear.

He further thinks if the trend doesn't reverse itself, there could be risk to consensus estimates forIntel and AMD. (Some analysts actually argue Intel could gain from Nvidia's pain—especially if there is a shift to the kind of integrated chipsets Intel makes.)

My take: You can slice these numbers anyway, but it would appear either PC growth is slowing or there was a bunch of double-ordering and shipping. And perhaps most importantly, PC pricing earlier this year was up for the first time in years due to component shortages.

If this glut continues, that's likely to reverse, along with PC pricing and industry revenues.