Will flash memory replace hard drives in notebook computers? Micron's CEO, Steve Appleton, thinks they will. Seagate CEO Bill Watkins thinks they won't. Why do these two CEOs think the way they do? In a Business Week article, Appleton is reported as thinking that flash memory will replace hard drives in notebooks.

Late last year Intel and Micron teamed up to manufacture NAND flash memory with Apple as a customer for the two.

In July this year Micron and Intel announced they are sampling the industry’s first NAND flash memory built on industry-leading 50 nanometer (nm) process technology. A 90nm process was used in 2004. The 50nm process will enable higher density flash memory chips. Micron has also joined a sub-32nm Flash research program.

The 50nm process has produced 4Gbit sample chips. Micron is clearly seeing its manufacturing roadmap to produce denser (= higher capacity) Flash continuing.

In a Cnet article Appleton said: "Any time a solution for storage, permanent storage…can be addressed for $50 or $60 or less, the mechanical guys are out and the solid-state guys are in."

"Why is that? It's because it's just basically impossible to get the cost below that $50 or $60 level for the mechanical guys, because it is mechanical - lots of moving parts. Certain things have to happen. So any time that happens, solid state is in, and mechanical's out."

"We're dropping our cost at 35 percent to 40 percent per year. That means you get more - you get 40 percent more - memory for the same price every year. The average notebook has 30 gigabytes (of hard drive storage). How long is it before the notebook has solid state memory? Five or six years."

In other words, by 2012 30GB of Flash memory for a notebook will cost less than $60. It will boot up far quicker than hard drive notebooks and its battery life will be longer.

Samsung, the world's largest Flash supplier, is already offering a 32GB Flash drive for notebooks. But it costs far more than $60, in fact about $1,175. Applying the 40 percent a year cost reduction we arrive at $55 in 2012, that's $1.72/GB.

Seagate's Watkins is dismissive. Far from 30GB his average notebook drive offering is 70GB. He doesn't think power consumption will be a factor in notebook purchases at all: "Power consumption won't be anything that people will pay anything for. What it's going to come down to is price per gigabyte."

He thinks Seagate and other hard drive manufacturers have an advantage because it's relatively easy for them to increase drive capacity by adding platters. It's relatively costly for Flash manufacturers to increase capacity because they combine basic chips, and they each have a price. If 4GB of Flash costs $5 then it's $40 for 32GB and $80 for 64GB. The cost per GB is a constant $1.25.

The rate of hard drive capacity growth and cost/GB decline is such that: "In three years we would say the average notebook drive will be 250 GB and they'll be selling for $45." That's $0.18/GB.

Using the 40 percent flash cost reduction per year, when will 32GB of flash cost $0.18/GB? In 2016 it will cost $0.22, reaching $0.13 in 2017. That's eight years after Seagate's predicted 250GB notebook hard drive.

If Appleton is right then notebooks with 32GB storage capacity will go Flash in 2012. If Watkins is right they won't because disk will have a phenomenal cost per GB advantage.

For example, in 2009 Seagate's 250GB hard drive is $0.18/GB whereas Flash will be $7.93/GB; that's 44 times more expensive. The economics appear to be in Seagate's favour.

No doubt some boot time-sensitive and battery life-sensitive notebooks will use Flash memory then but the bulk of the market should be using spinning platters still, and for many years after that too.

Game, set and match to Seagate? It looks like it.