A lack of economic confidence in Europe could also contribute to the slowdown in PC shipments, Daoud said. That is a big change from the same quarter a year ago, when record PC shipment growth came as economies were exiting the recession.

There was a lot of interest in PCs when Windows 7 came out, but the excitement has dried up, so consumers are trying to extend the life of their PCs, Daoud said.

"What we are seeing now may be part of a correction ... plus a very difficult [economic] environment out there," Daoud said.

While Daoud said a straw poll would suggest a lot of interest in tablets, there is not empirical evidence yet to suggest that tablets are directly hurting PC shipments, which are much larger in volume. Tablets are used as secondary computing devices to PCs, but as new usage models emerge, tablets could "cannibalize" PC shipments over time, Daoud said.

The top three PC vendors -- Hewlett-Packard, Dell and Acer -- saw PC shipments fall year over year due to lackluster demand for products. However, fourth-placed Lenovo saw shipments grow by 16.3 percent due to strong demand for its products in China and a disciplined channel expansion worldwide.