Voodoo Blog

[#1]

This is an extended version of the article I wrote for the latest edition of Custom PC Magazine in the U.K. Once again, if you're looking for the sexiest PC Hardware Magazine in Europe (and one of the best in the world) you should get his magazine! It's full of the best hardware photography ever, and the quality of the paper is to die for.

Toms Hardware just wrote an interesting article called The SSD Power Consumption Hoax.

While they have some interesting points, I would suggest that there is much more involved with evaluating the potential increase in battery life with Solid State Technology.

A Solid State Drive can affect battery life in two situations: 1) Poor Performance, and 2) High Idle Power.

You cannot estimate the power savings of a solid state drive simply by looking at the hard drive subsystem and then extrapolating based on datasheet power specifications. That methodology does not comprehend the work being performed, and performance impacts energy efficiency. If a solid state drive can complete a workload 2x faster than a hard drive, then the entire platform can enter a power efficient state sooner.

We suspect that one reason that Tom's measured worse solid state battery life than a 7200 RPM HDD is likely that the particular solid state drive performed worse than the 7200 RPM HDD.

If the solid state drive completed the workload later, then the platform consumed more power. It also appears Tom’s chose solid state drives that use FPGAs, and these devices probably have very high idle power.

So bottom line is that power efficiency must comprehend the work being performed (during the power measurement.) A better metric is power per IOs per second. I know of at least one solid state drive that consumes only 60mWatts during idle, and it consumed less than 100mW on average in Mobilemark.

...and uhhh, a mobile hard disk drive consumes between 1 and 1.5 watts during a Mobilemark run.

So, does this mean that Tom's Hardware was right? Perhaps with their specific benchmarks - but even unintentionally, it's a pretty glorified "lets be controversial" slightly narrow view of the world. I'm not going to tear it apart - but it seems the author assumes that all solid state drives are created equal. There is a profound difference in performance and power depending on the product architecture and design. Tom's itself reported up to a 10x span in solid state drive raw performance depending on vendor, so it's interesting that this author assumed they are generic.

To put it in perspective, even if the hard drive were removed entirely, it only represents ~5% of the total battery consumption. So even if we halve the consumption with solid state we'd typically only gain 10 minutes battery life (out of 3 hours). Therefore a solid state can have a slight improvement on battery life. So what's the point of even writing about it? Ugh, wasting my time.

Trust me, this is NOT the end of the story. Stay tuned for later this year when the solid state $@#* hits the fan and spinning disk heads start to roll. There are some new players in town and they are bringing the big guns.

rs

www.rahulsood.com

Message Edited by Rahul on 07-03-2008 05:57 PM

[#2]

Thank you so much for the article and response to Tom's Hardware. This really opened up my perspective on things. Everytime I see some type of article against SSD, but when reading yours, I see factual evidence and reasoning behind the defense of SSD.

Much appreciated. I am a huge SSD supporter in the sense that I believe that it is the present and future and there is so much potential out there for it beyond the potential for HDD. These are boards with chips, fully electronic, the possibilities are endless compard to a machanical device with platters. Let us also know in the future how everything turns out with the SSD by Samsung in the Envy 133.

Thanks again.

[#3]

This is a bit reminiscent of what happened with displays. For many years it seemed like there would never be a widely successful challenge to CRT technology. Early flat panels were expensive and cost/performance seemed like it would never get there. Finally the technology got cheap enough and good enough and we hit the knee in the curve where all of a sudden flat panels became mainstream.

I also worked on 1.3" disk drive technology. It was whizzy stuff at the time, but flash outpaced it before it ever made it to market.

Disk drive technology has had an incredible run. But that will be over someday. Maybe soon. The transition to SSD is inevitable. The knee in the curve is not that far off IMO.

[#4]

Why did you pick the Samsung SSD, it sucks. memoright currently makes the fastest SSD drive, which is near in speed to the velociraptor, which is 120mb/sec. The Samsung drive can only do 55.9Mb/sec and has been proved by our SSD master, Les on NBR. You really should have done a bit more research and bought either the M-TRON 7000 series or the Memoright GT
I would recommend having Voodoo give you a standard mechanical drive and then upgrading to the memoright drive since it has superior read/write speeds.

SSD tech has been terrible over the last two years, and it is really starting to get better. The main reason why SSD's are so low in capacity is because the more memory cells you have the more power is drawn. These memory cells use power regardless of whether they are being used or not. SSD's are becoming better and more power efficient because they are using qimonda and Samsung memory cells which can deliever up to 4 and 8gb of capacity on a single chip. These are ungodly expensive but they will go down in price over the next few years.
But right now, your best bet is putting your money on a mechanical disk since they have been perfected while SSD's are only just being introduced. Buying an SSD today will be completely outdated in a year or so, as the technology advances, right now I feel it is a complete waste, but in a year or two the prices will be more affordable and SSD's will have more reliabilty.

K-TRON

[#5]

K-Tron, the memoright drives are faster, but they also cost around $2000. The samsung has a little more than half the performance for about a quarter of the price, so it's still a better value. And keep in mind that just because a faster drive is used it may not 100% translate to faster performance overall. With something too fast everything will just bottleneck on the processor or memory. So.. the memoright drives will be awesome when the price comes down, but they really aren't right for an ultraportable. And this is assuming memoright makes drives that fit the envy for the same price as their regular drives which is highly unlikely.