EL SEGUNDO, CA -- Global PC shipments will be dragged down in 2012 thanks to the shortfall in hard disk drives.

IHS lowered its first-quarter outlook by 3.8 million units and now predicts 6.8% in 2012, down from its August outlook of 9.5%.

IHS predicts first-quarter worldwide PC shipments will reach 84.2 million units, down from an earlier forecast of 88 million.

First-quarter shipments will decline 11.6% sequentially from 95.3 million units in the fourth quarter, IHS said, far sharper than the 6% historical average decline.

Total PC unit shipments in 2012 are forecast to amount to 376 million, compared to the previous prediction of 399 million, partly due to the HDD shortage, along with weakening demand due to other factors.

The bulk in reduction in shipments will be in the notebook space, which is the area impacted by the HDD shortage. Notebook PC shipments now are expected to rise by 10.1% in 2012, down from the previous forecast of 13.8% growth. "The PC supply chain says it has sufficient HDD inventory for the fourth quarter of 2011. However, those stockpiles will run out in the first quarter of 2012, impacting PC production during that period,” said Matthew Wilkins, senior principal analyst, compute platforms for IHS.

Starting in the first quarter of 2012, the HDD supply situation will begin to improve. It will take time, however, to replenish the supply chain, with overall HDD industry supply expected to meet demand only by the end of the third quarter of 2012. Already, the major HDD suppliers have shifted production to locations outside of Thailand, which will help ease the shortage situation.

PC shipments should rebound from the HDD shortage in the second half of the year. Still, total shipments for 2012 will fall short of previous expectations because of economic factors and rising competition from media tablets.

Ironically, the HDD market could face an inventory surplus by the end of 2012, after facilities in Thailand return to full production, IHS said. When combined with the added production outside the country, the recovery in Thailand’s HDD operations could result in excess supply.