Microsoft's Windows 8 took another knock Wednesday as research firm IDC laid much of the blame for the first quarter's historically-horrible PC numbers at the feet of the beleaguered operating system.

Yesterday, IDC and rival Gartner released their estimates for 2013's first-quarter PC shipments. The former painted a gloomy picture of the industry, saying that the 14% decline, year over year, was the largest ever in its nearly two decades of tracking.

Gartner pegged the global downturn at 11%.

While the drop was expected -- IDC, for example, had forecast an 8% contraction year over year -- yesterday's figures had one analyst searching for words. "It's brutal," said Bob O'Donnell of IDC. "These are disastrous numbers. Huge."

O'Donnell was one of the IDC analysts who blamed Windows 8 for the unprecedented fall-off in consumer PC purchases during the quarter. "Not only has Windows 8 not helped, but it's actually hurt PC shipments," he said in an interview.

In a statement that accompanied the firm's estimates, O'Donnell ticked off a now-familiar litany of Windows 8's confusing traits that caused consumers to shy from new PCs, including the bold-but-radical move to the tile-based "Modern" user interface (UI), the removal of the Start button and menu from the "Classic" desktop UI; and the touch-first strategy Microsoft's taken.

"The costs associated with touch PCs have made PCs a less attractive alternative to dedicated tablets and other competitive devices," O'Donnell said in the statement. "Microsoft is going to have to make some very tough decisions moving forward if they want to help reinvigorate the PC market."