HDD – The SSD Guy Blog

HDD & SSD Combined Into One

The SSD Guy has often explained to readers that the storage industry is caught between two alternatives: fast and costly, or cheap and slow. This is the key difference between SSDs and HDDs. I have recently learned of a new secret government research effort, code named “SiliDisk,” that will provide the best of both worlds by marrying flash memory with the mechanics of an HDD.

The approach is incredibly ingenious, while remaining deceptively simple: All that is required is to replace the disks in an HDD with the wafers used to manufacture NAND flash. Both are round, so there’s little engineering effort to switch from a magnetic disk to a flash wafer.

The NAND flash on the wafer is almost completely standard. The only two changes are that the chips aren’t scribed or sawn apart, saving a small sum, but a hole must be etched through the center (which can be seen in the photo below) offsetting this savings. The HDD mechanisms are unchanged with one exception: While today’s HDDs are largely manufactured using 2.5″ and 3.5″ platters (65mm & 90mm), NAND flash is exclusively produced on 300mm wafers. This means that Continue reading “HDD & SSD Combined Into One”

WDC: No SSD/HDD Crossover

Those who have been reading posts on The SSD Guy blog for some time have often heard me explain that SSD prices will not fall below HDD prices anytime soon. Last week Western Digital shared a roadmap that shows that we can expect for there to be a sizeable price gap between the two technologies at least through 2028.

Let me stop for a moment to point out that Western Digital Corp, or WDC, no longer has any reason to take sides in the HDD vs. SSD battle now that the company has acquired SanDisk, a leading SSD maker. Even before that, WDC’s HGST business has been the market leader in SAS SSDs for a number of years. WDC doesn’t take sides in arguments about SSDs vs. HDDs. Instead the company stands ready to sell whichever one the customer finally decides to use.

This post’s graphic comes from a chart that WDC used on October 11 when introducing its new MAMR head technology, which the company expects to propel HDD capacities up, and HDD price per terabyte down, for a number of years. To create this chart WDC’s HDD team joined forces with the SanDisk flash team to project both HDD and NAND price per terabyte for the next 11 years. The most important conclusion is that Continue reading “WDC: No SSD/HDD Crossover”

Why SSD and HDD Prices Move in Parallel

Why are HDD prices tracking SSD prices? Why don’t they cross over? These are questions that The SSD Guy is often asked, especially by people who anticipate a crossover in the near future.

In essence it’s because both the HDD industry and the semiconductor industry have set goals for themselves to achieve 30% average annual price reductions. If they are both on the same trajectory, and if there’s an order of magnitude difference between HDD and SSD prices today, then there will be an order of magnitude difference in the future as well.

The 30% average annual decline in SSD prices has a convenient name: Moore’s Law. Although there’s no physical, economic, or other restriction behind Moore’s Law (so it’s not really a law at all) it serves as a guide for the industry. Chip makers set their sights at doubling the number of transistors on a chip every couple of years, and this equates to average annual price decreases of 30%.

The HDD business also Continue reading “Why SSD and HDD Prices Move in Parallel”

Toshiba Reveals Restructuring Plans

On Friday Toshiba revealed its restructuring plans aimed at returning the company to profitability and growth through management accountability.

Of special interest to The SSD Guy was the fact that the company will refocus its semiconductor and HDD businesses, currently called the “Semiconductor & Storage Products Company” partly by giving it a new name: “Storage & Electron Devices Company”. This division will focus on the semiconductor group’s good prospects and profitability while maintaining a focus on the fact that SSDs and HDDs share a business. In the not-too-distant past Toshiba has run these two businesses separately.

The group plans to be “A pillar of income with Memories as a core business”. To achieve this, Toshiba has stated that it will enhance its NAND cost competitiveness by accelerating development of BiCS (Toshiba’s 3D NAND technology) and by expanding the SSD business. There are three parts to this Continue reading “Toshiba Reveals Restructuring Plans”

Why Aren’t SSDs Popular in New PCs?

For the past decade I have been asked when SSDs will overtake HDDs in the PC market- when will more PCs ship with an SSD than with an HDD?

My usual reply is: “Never!” I then go on to explain that two factors work against this ever happening. The first is the fact that SSD prices are unlikely to ever match HDD price per gigabyte, which is the subject of a few posts on The SSD Guy, the most recent appearing HERE. The second reason is that most PC buyers find SSDs unappealing when they are shopping for a new PC because of the price difference between an SSD and an HDD of the same capacity.

There are six Continue reading “Why Aren’t SSDs Popular in New PCs?”

Big New HDDs Indefinitely Postpone SSD/HDD Price Crossover

Earlier this month Western Digital’s HGST division invited The SSD Guy to a launch of a number of products. On the HDD side there were:

6TB air HDD, HGST’s last air-filled enterprise HDD
8TB helium HDD, an incremental upgrade of last year’s 6TB helium HDD
10TB shingled helium HDD (pictured)

I view these as very solid evidence that HDD costs will continue to stay an order of magnitude cheaper than SSD costs, thwarting the price-per-gigabyte crossover that others have been predicting for years.

In fact, since my last post on the price crossover in 2011, very little has changed.

It’s safe to assume that the HDD industry will Continue reading “Big New HDDs Indefinitely Postpone SSD/HDD Price Crossover”

Are HDDs Vibration Sensitive?

One reason to use SSDs is that, with no moving parts, these devices are insensitive to shock and vibration. HDDs, on the other hand, are sensitive enough to vibration that it can cause access delays.

How sensitive are they? Well, I have seen some overblown claims from SSD makers that shock will cause HDD head crashes. I am not sure that I believe such claims, but I certainly do believe that an HDD’s actuator (the read/write head mechanism) can be shaken away from its track, causing a Continue reading “Are HDDs Vibration Sensitive?”

Apple’s Fusion Drive – An SSD Cache for the Macintosh

On October 23 along with the highly-anticipated announcement of the iPad 4, Apple rolled out new Macintosh computers that for the first time in an Apple product pairs an SSD with a conventional HDD to get the best combination of capacity, speed, and price. The company calls this its Fusion Drive, not to be confused with Fusion-io’s highly-regarded products.

The SSD Guy did not attend the announcement, and there is little on the Apple website. I contacted Apple, and they don’t have very much detail to share at this time. This is important to note, since Continue reading “Apple’s Fusion Drive – An SSD Cache for the Macintosh”

For the Lack of a Fab…

SanDisk-Toshiba Yokkaichi Plant from WD 2007 IDEMA Presentation One popular argument to explain why SSDs have not displaced the HDDs in all PCs is that there isn’t enough NAND flash production capacity to support this business and there never can be.

This argument has been posed as long ago as 2007 by WD CEO John Coyne at an IDEMA conference (the source of this post’s graphic), SanDisk’s Eli Harari at the Flash Memory Summit in 2008, and Seagate‘s CEO Steve Luczo in a Forbes interview as recently as last April. These are captains of the industry. Their arguments make people stand up and take notice.

It’s a really flawed argument.

It goes like this: Continue reading “For the Lack of a Fab…”

Seagate Invests in DensBits

Seagate today announced an investment and technology agreement with DensBits, an Israeli SSD controller company mentioned by The SSD Guy in another post.

According to the press release Seagate will use DensBits’ technology for “consumer and enterprise applications including 3 bits/cell (“TLC”) 1Xnm Flash-based consumer-grade SSD, and 2 bits/cell (“MLC”) 1Xnm Flash-based enterprise-grade SSD.”

A pattern is starting to emerge. We understand that Seagate’s current Pulsar SSDs use chips from Link_A_Media (the subject of another recent post) which has only recently Continue reading “Seagate Invests in DensBits”