In 1985, Intel released the 80386, a particularly complex and sophisticated microprocessor for its day, consisting of 275,000 transistors, a rather large number for the day.

How many transistors went into the accompanying 80387 floating-point coprocessor?

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    12. Though I did calculate that on my first-gen Pentium. – TonyM Nov 18 '20 at 14:35

I’ve wondered about this for a long time — manufacturers don’t seem to communicate FPU transistor counts as readily as CPU counts.

The best I’ve found so far is a claim on coprocessor.info that the 80387 contained approximately 120,000 transistors (quite a bit more than the 8087’s 45,000 transistors).

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    For comparison, the Cyrix FasMath 83D87 (socket compatible with the 80387) contained about 375,000 transistors. See: Tom Brightman, "Advancing the Standard in Floating-Point Performance", High Performance Systems, Vol. 10, No. 11, November 1989, pp. 59-64 – njuffa Nov 19 '20 at 1:32

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