The CDC 8600 was the last of Seymour Cray's supercomputer designs while working for the Control Data Corporation. The "natural successor" to the CDC 6600 and CDC 7600, the 8600 was intended to be about 10 times as fast as the 7600, already the fastest computer on the market. Development started in 1968, shortly after the release of the 7600, but the project soon started to bog down. By 1971 CDC was having cash flow problems and the design was still not coming together, prompting Cray to leave the company in 1972. The 8600 design effort was eventually cancelled in 1974, and Control Data moved on to the CDC STAR-100 series instead.