Between unimaginative products, competition from tablets and smartphones, the flood-created squeeze on hard drives and high prices, PC shipments dropped somewhere between 0.2% and 1.4% in the fourth quarter compared to 4Q10 according to IDC and Gartner. IDC is the more optimistic one. And remember Q4 is usually strong because of the holidays.

HP was the author of its own peculiar problems. Although still the sector's leader it shipped 14.7 million boxes in Q4, 16% fewer units than the year before because of doubts over the fate of its PC unit.

The brunt of the component shortages are only beginning to be felt, Gartner said, casting a lengthening shadow over the market's performance in the months ahead and consumers may also delay purchases in anticipation of Microsoft's new Windows 8 operating system coming out in the second half. Since Windows 8 is being optimized for tablets, that may have an additional impact. It is unclear whether an onslaught of Ultrabooks will tickle laptops.

IDC thinks shipments this quarter could be down 5.1%.

PC shipments worldwide ranged somewhere between 92 million and 93 million in Q4. HP owned 16% of the market, down from 19%, followed by Lenovo with 14%, up from 11%, and Dell with 13%. Lenovo's shipments were up 23% to 12.9 million PCs by Gartner's count, 37% by IDC's. It has ambitions to dethrone HP.

Demand fell 6%-7% in the US to around 71.3 million units, which a surprised IDC said represented the biggest year-over-year quarterly drop in America since 2001. It had expected the US to be flat.

In the states the top PC vendors were HP, down 26% to 4.1 million units, Dell, down 5%, and Apple, the only company to register year-over-year growth. HP lost six point of market share when it came in with only 23%. Dell is at 22%. Mac shipments grew about 21% and Apple now owns nearly 12% of the US market.

Demand was even worse in Western Europe, which is being tortured by economic demons. PC shipments in EMEA were off 9.6% at 28.9 million units.

Gartner said growth on the commercial side and in emerging markets wasn't able to compensate for the weakness in the mature markets.

Worldwide shipments for all of 2011 totaled 352 million-353 million, with Gartner figuring that means they were up 0.5% and IDC 1.6%.