NEW YORK — U.S. shipments of personal computers are expected to drop nearly 3 percent next year, while demand in much of the rest of the world will slow down quickly as the financial crisis spreads, research firm IDC said Wednesday.

That could be bad news for two of the world's largest PC manufacturers who have major operations in North Carolina.

Lenovo, which ranks No., maintains its global headquarters in Morrisville.

And Dell, which is No. 2 behind world-leader HP, operates its largest manufacturing plant in Winston-Salem, N.C. Acer ranks third in sales. It is absed in Taiwan.

IDC, which said last month it expects global technology spending to slow significantly next year, now forecasts worldwide 2009 PC shipment growth of 3.8 percent, with the value of those shipments falling by 5.3 percent. This is down considerably from IDC's earlier projection, made during the second quarter, of a 13.7 percent growth in units shipped and 4.5 percent increase in PC revenue.

Emerging markets in Latin America, Central Europe, the Middle East and Africa had seen some of the fastest growth in recent years, as falling PC prices helped drive sales higher. But now the picture is changing quickly. The rising value of the dollar and restricted credit have had a "dramatic" effect on the ability for computer buyers, distributors and retailers to obtain financing, IDC said. Asia, excluding Japan, will likely be the fastest-growing region.

IDC expects U.S. PC shipments to decline by nearly 3 percent in 2009, with low single-digit growth in the following three years.

That would make 2009 the first year of decline since 2001, when shipments plunged 12 percent, and could increase the pressure on already-struggling PC makers such as Dell Inc. For the current quarter, the research firm expects about a 1 percent decline, said Loren Loverde, director of IDC's Worldwide PC Tracker program.

Overall, portable PCs are expected to fare much better than their desktop counterparts. IDC expects portable computer shipments to grow by 15.2 percent next year, but it forecast a decline of 6.7 percent in desktop PCs and servers that use PC microprocessors. The rising popularity of cheaper mini-notebooks, or "netbooks," will help shipment volumes, but hamper PC makers' profit margins.