storage medium for music and video games. NEC had been the first to use CD technology in a video game console with their PC Engine CD-ROM² System add-on in October 1988 in Japan (launched in North America as the TurboGrafx-CD the following year), which sold 80,000 units in six months. That year, Nintendo announced a partnership with Sony to develop a CD-ROM peripheral for the Super Nintendo Entertainment System (SNES). Commodore International released their CD-based CDTV multimedia system in early 1991, while the CD-i from Philips arrived later that year. According to Nick Thorpe of Retro Gamer, Sega would have received criticism from investors and observers had it not developed a CD-ROM game system. Development Shortly after the release of the Genesis, Sega's Consumer Products Research and Development Labs, led by manager Tomio Takami, were tasked with creating a CD-ROM add-on. It was originally intended to equal the capabilities of the TurboGrafx-CD, but with twice as much random-access memory (RAM). In addition to relatively short loading times, Takami's team planned to implement hardware scaling and rotation similar to that of Sega's arcade games, which required a dedicated digital signal processor. A custom graphics chip would implement these features, alongside an additional sound chip manufactured by Ricoh. According to Kalinske, Sega was ambitious about what CD-ROM technology would do for video games, with its potential for "movie graphics", "rock and roll concert sound" and 3D animation. However, two major changes were made towards the end of development that dramatically raised the price of the add-on. Because the Genesis' Motorola 68000 CPU was too slow to handle the Sega CD's new graphical capabilities, an additional 68000 CPU was incorporated. This second CPU has a clock speed of 12.5 MHz, faster than the 7.67 MHz CPU in the Genesis. Responding to rumors that NEC planned a memory upgrade to bring the TurboGrafx-CD RAM from 0.5 Mbit to between 2 and 4 Mbit, Sega increased the Sega CD's available RAM from 1 Mbit to 6 Mbit. This proved to be a technical challenge, since the Sega CD's RAM access speed was initially too slow to run programs effectively, and the developers had to focus on increasing the speed. The estimated cost of the device rose to US$370, but market research convinced Sega executives that consumers would be willing to pay more for a state-of-the-art machine. Sega partnered with JVC, which had been working with