Начиная с первых пентиумов эта кнопка действительно стала чисто декоративной, тут ты прав. Но я писал про машину, на которой лично работал в 1990 году, 32 с половиной года назад (СФ МЭИ, электромеханический факультет). Кнопка "турбо" там реально работала. Машинка не была уникальной, подобные выпускались, к примеру, Eagle Computers. Цитирую PC Tech Journal за июль 1984 года: "Eagle Computer Inc. introduced an upgrade to the Eagle PC to be called the "Eagle PC Turbo GT" (at first I thought it was a sports car). The 8086-based machine has a "Turbo" button on the front panel. Press it and the machine switches from the PC/XT compatible clock speed of 4.77 Mhz to 8 Mhz. High-speed RAM chips are used with no wait states, so that the machine runs at full speed with performance claimed to be two to three times faster than the standard IBM PC/XT" или декабрьский номер PC Magazine за тот же 1984 год: "The new Eagle uses an 8086 CPU with an 8-MHz clock and a 16-bit data path. Compared with the IBM PC's 8-bit (data path) 8088 which clocks in at just 4.77 MHz. the PC Turbo is a very fast engine indeed, even without adding the optional 8087 coprocessor in the empty socket provided for it. In fact, it is so fast that Eagle had to include a front-panel pushbutton to slow down operations by inserting extra wait states when required for PC-compatibility. The Norton Syslnfo diagnostic program rated the speed of the Eagle PC Turbo-XL in its slow mode at 1 .4 times that of the PC, and full-bore performance measured 1.8 times the PC's speed".