The single-core AMD Athlon 64 L110 processor is being used by Gateway in the LT3103u netbook, which was announced earlier this week. This is AMD's first chip to reach netbooks, which are laptops with small screens designed for basic tasks like Web surfing and word processing. Gateway is owned by PC maker Acer.

The low-voltage processor is a variant of the Neo chips that AMD has designed for thin and light laptops, which have larger screens and offer more functionality than netbooks. The Athlon 64 L110 chip runs at a clock speed of 1.2GHz, has 512KB of cache and draws about 13 watts of power.

Most netbooks today carry Intel's Atom chips, with Via's low-power Nano processor in a distant second place. AMD in the past has derided netbooks, saying that though the PCs were inexpensive, they didn't offer full functionality.

So the sudden emergence of an Athlon chip in a netbook comes as a surprise, especially because AMD has repeatedly said it would not enter the netbook space. The company still maintains a stance of not being interested in netbooks, but a spokesman softened that rhetoric on Thursday.

"AMD has fully anticipated that our technology would eventually appear at the upper end of the netbook space," said Steve Howard, an AMD spokesman. Though the chip was designed for ultrathin notebooks, AMD did not want to restrict the desire of PC makers to use it in different form factors, he said.