While PC microprocessor sales increased year over year in the third quarter, economic uncertainty and softer-than-expected demand have caused IDC to cut forecasts for the market this year.

Worldwide PC microprocessor revenue in the third quarter rose to US$10.7 billion, up by 12.2 percent compared to the prior quarter and up 16.1 percent year on year, according to .

However, IDC said in its report Thursday that it is cutting its growth forecast for the market from 9.3 percent to 7.3 percent for the year.

"Combined with a weak macroeconomic outlook -- due to sovereign debt issues in Europe and poor job growth in the United States -- IDC is reducing its client PC processor (desktop, mobile, x86 server) unit growth forecast for 2011," the company said.

In its own report earlier in the week, despite flat-to-slow growth in PC shipments worldwide over the past year.