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Theophylact · August 18th, 2002, 04:42 PM

It's an old story.

The Intel 486 came in two versions: the 486, with math coprocessor, and the 486SX, "without" coprocessor. The chip itself was the same (why have two fabrication facilities?) but one version had an extra pin to enable (or disable, I can't remember which) the coprocessor.

Back in the days when IBM didn't sell you its machines, only lease them (that is, before the antitrust consent decree), they had a punch card reader that came in two versions: a less-expensive, slower one and a more-expensive, faster one. You could pay for an upgrade, though, and if you did, what happened was that an IBM systems engineer would come, open a side panel, and switch the drive belt from one set of pulleys to another.

It's the kind of thing that lends credence to urban legends like the 200 Mpg Carburetor.

August 18th, 2002, 04:42 PM	#4 (permalink)
Theophylact Fossil Join Date: Oct 2001 Location: inside the Beltway Posts: 6,433 Blog Entries: 41	It's an old story. The Intel 486 came in two versions: the 486, with math coprocessor, and the 486SX, "without" coprocessor. The chip itself was the same (why have two fabrication facilities?) but one version had an extra pin to enable (or disable, I can't remember which) the coprocessor. Back in the days when IBM didn't sell you its machines, only lease them (that is, before the antitrust consent decree), they had a punch card reader that came in two versions: a less-expensive, slower one and a more-expensive, faster one. You could pay for an upgrade, though, and if you did, what happened was that an IBM systems engineer would come, open a side panel, and switch the drive belt from one set of pulleys to another. It's the kind of thing that lends credence to urban legends like the 200 Mpg Carburetor.