Intel's Pentium 4 for mobile computers will come out at speeds above 1.5GHz in the first half of next year, but it won't be matched with memory based on technology from Rambus. The Pentium 4, which currently is available only in desktops, comes to notebooks by virtue of a manufacturing shift that cuts the power consumed and heat dissipated by the chip, said Bob Jackson, principal engineer in Intel's mobile processing group. By cutting the power, Intel can squeeze the chip into portables. "You need to keep the average power down to about 10 percent of the overall power" consumed by the notebook, Jackson said at the Microprocessor Forum in San Jose. The first mobile Pentium 4's arrive in the first half above 1.5GHz and will hit 2GHz in 2002. But unlike the first Pentium 4's for desktops, the chip won't initially be matched with memory based on designs from Rambus. Instead, the mobile Pentium 4 will come out with a chipset--called the 845MP--that connects to DDR DRAM, a high-speed form of the most common type of memory found in PCs today. Although it can provide performance benefits, Rambus memory costs more than other types of memory. Consequently, PC makers have tried to avoid it whenever possible. Intel came out with its first Pentium 4 chipset that hooks up with standard memory in February, and PC makers have flocked to it, according to analysts and PC executives. Many analysts have predicted it could be one of Intel's most popular chipsets ever. The mobile Pentium 4 will also contain other features, including an enhanced form of SpeedStep technology. With SpeedStep, notebook chips run at a lower speed when unplugged to save on battery power. In the enhanced version, notebooks can run at 95 percent of their "plugged in" speed if required by the application. After the performance surge passes, the notebook returns to its slower, unplugged standard. "You don't sacrifice on battery life, but you get the performance when you need it," Jackson said. The reduction in power consumption comes from improvements in transistors and a shift in manufacturing from the 180-nanometer process to the 130-nanometer process. Under the 130-nanometer process, the size of the components on the surface of a chip are shrunk by roughly 30 percent to 130 nanometers wide. Shrinking moves all the elements together, which cuts down on power consumption. Although chips shrunk by this process can consume less power, these gains can be nullified over time as the speed of the chip increases. CNET News.com's Michael Kanellos reported from San Jose, California. See Chips Central for the latest headlines on processors and semiconductors. See the Hardware News Section for full coverage. Have your say instantly, and see what others have said. Click on the TalkBack button and go to the Chips Central forum Let the editors know what you think in the Mailroom. And read other letters.