TEXAS Instruments has expanded its consumer product line with the introduction of the Extensa family of notebook computers. Available in three models, the new notebooks are expected to make portable computing more affordable for home office and small business users. The three models - the 450/450T, 550 and 550CD/550CDT - come in various configurations with the lowest-end model featuring an Intel DX4 75-megahertz processor and four megabytes of random access memory, and the highest-end notebook coming with a Pentium 75-MHz microprocessor with eight MB of RAM. Hard disk capacity ranges from a 340-megabyte drive that comes standard with the 450/450T models to a 524-MB drive in the 550CD/550CDT notebooks. All three models have a 10.4-inch dual scan screen, although the 450T and 550T are available with 9.4-inch thin film transistor active matrix screens. The Extensa range also includes nickel metal hydride batteries that go a long way towards eliminating the memory effect in older nickel cadmium batteries. TI has also equipped the new models with touchpad technology pointing device, a trend that is growing among notebook computer makers. Prices of the Extensa family start at $16,500.