[prr]

12 cycles of Moore's Law puts that 3.56 million figure at $869.14. Unlocked cost on the Apple store: $749

[baddox]

Strictly speaking, Moore's Law doesn't say anything about price, but I suppose that's implied.

[fortepianissimo]

Could it be because the estimate already took Moore's law into account?

[fortepianissimo]

Care to detail your calculation?

[prr]

$3 560 000 divided by 2, 12 times :-)

The effect of Moore's "law" is that processing power doubles approximately every 2 years, while the cost halves.

If 1 "unit" of processing currently costs $1; in 2 years time, 2 units will cost $1. Or that 1 unit costs 0.50.

[T-hawk]

Moore's law is that the density of discrete components (transistors, storage cells) increases. Cost and speed are knock-on effects. It just so happens that density does drive CPUs to be faster for the same production cost and storage to be either more capacious or physically smaller. But some aspects of computing performance don't benefit from density, like memory response time for example.

[Galactor963]

Divided by two for each cycle (each doubling of transistors). 3560000/2^12 = 869.140625

[baddox]

Just cut 3.56 million in half 12 times.

    3,560,000 * 0.5 ^ 12 ≈ 869.14

[lutusp]

I offer this notational suggestion, just to avoid either a floating-point or fractional constant:

3,560,000 * 2 ^ -12 ≈ 869.14

Based on: 1/2 ^ 12 = 2 ^ -12

[baddox]

That's much less clear if someone isn't aware of how negative exponents are defined. That's why I chose this notation, and why I put into words "cut in half 12 times."

[lutusp]

> That's much less clear if someone isn't aware of how negative exponents are defined.

Yes, I've noticed that in other contexts. It's too bad because it makes the representation less clear, more complex than necessary. I first became aware of this when I tried to say that gravitational force declines as r^-2, to numerous protests.

Oh, well -- a tempest in a teapot, as they say.