Production at the North Carolina plant that Dell Inc. is closing in Winston-Salem will be moved to Mexico and other countries, according to a federal document.

Dell Inc. says it has agreed to buy the information technology services company Perot Systems Corp. for about $3.6 billion as it looks to expand beyond the personal computer business.

Dell Inc. says the U.S. personal computer market has reached its low point. But the timing of a global turnaround in the technology industry remains anyone’s guess.

With Dell Inc.‘s new $2,000-andup laptop, the computer maker entered the ultrathin notebook race yesterday. The Adamo, from the Latin for “to fall in love with,“ is an aluminum-body laptop that comes in two colors, “onyx” and “pearl.“ It boasts a 13-inch screen and, with a depth of less than two-thirds of an inch, is thinner than both Apple Inc.‘s 0.76-inch MacBook Air ($1,800 and up) and Hewlett-Packard Co.‘s 0.7-inch Voodoo Envy notebook (from $1,900).