“Two years after the 99/4’s debut, TI released the 99/4A in 1981, very similar but with a better keyboard and more expansion options. By lowering its price from $1,150 to $525 and offering rebates TI sold many more computers. In the early 1980s, TI was known as a pioneer in speech synthesis, and a highly popular plug-in speech synthesizer module was available for the TI-99/4A. Speech synthesizers were offered free with the purchase of a number of cartridges and were used by many TI-written video games. The TI-99/4 series holds the distinction of being the first 16-bit personal computer. The TI-99/4A had a 16-bit TMS9900CPU running at 3.0 MHz.
It has been estimated that it had about 35% of the home computer market at its peak. In 1982 TI began a price war with Commodore International by lowering the street price of the 99/4A to $200, including a $100 rebate, to compete against the $300 Commodore VIC-20. TI was forced to sell the 99/4A for about the same price as the VIC-20, even though it was much more expensive to manufacture. After losing $111 million after taxes in the third calendar quarter of 1983, TI announced in October 1983 that it was discontinuing the 99/4A, while continuing to sell the TI Professional MS-DOS-compatible computer.”
– Information received from Old-Computers.com