The SSD Relapse: Understanding and Choosing the Best SSD
by Anand Lal Shimpi on August 30, 2009 12:00 AM EST- Posted in
- Storage
Power Consumption
SSDs are at their highest power consumption when performing large file sequential writes. The majority of the power consumption comes from writing to the NAND flash and when you’re doing sequential writes you have more flash devices engaged at a time. Thus my peak power consumption test involves measuring power used over the 5V rail while the drives perform my 2MB sequential write benchmark in Iometer and at idle of course.
First, the idle numbers:
The Samsung and Indilinx drives use the least power, while the Intel drives use the most out of the SSDs. Intel honestly just needs to stick some power gate transistors in front of the controller and flash to curb power consumption at idle. They are all still lower than a mechanical drive, and much lower than a 3.5" HDD.
It's also worth noting that given the order of magnitude performance advantage these drives hold over traditional hard drives, they spend far more time at idle than their mechanical counterparts.
Under load the SSDs use anywhere from 2.5 - 3.5W, the exception being the Indilinx SLC drive which comes in at under 2W. Power consumption is roughly half if you switch to a random write workload, and the standings also switch places. While Intel's X25-M G2 draws less power than the OCZ Vertex Turbo in the sequential write test, it draws more power in a random write workload:
| Random Write Power Consumption | Min | Average | Max |
| Intel X25-M G2 160GB (MLC) | 1.55 W | 1.60 W | 1.7 W |
| OCZ Vertex Turbo 128GB (Indilinx MLC) | 1.13 W | 1.17 W | 1.21 W |
As I alluded to before, the much higher performance of these drives than a traditional hard drive means that they spend much more time at an idle power state. The Seagate Momentus 5400.6 has roughly the same power characteristics of these two drives, but they outperform the Seagate by a factor of at least 16x. In other words, a good SSD delivers an order of magnitude better performance per watt than even a very efficient hard drive.
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Abjuk - Wednesday, September 2, 2009 - link
Agreed CM, my current project at work takes about six minutes to build from scratch and CPU usage never gets above about 35%. The process is totally IO bound.It really depends on whether you have several large source files or several hundred small ones.
Weyzer - Tuesday, September 1, 2009 - link
Good article and testing, but why was the Crucial M225 not mentioned at all? It's performance is similar to the vertex drives, I know, but I think it could have been mentioned somewhere, if it is in the good or bad range.jasperjones - Tuesday, September 1, 2009 - link
javascript:link('frmText') $997 @ Newegg omgomgomgNeedless to say, that price will come down quickly. So more seriously, after reading the article I really feel I understand better what to look for in an SSD. Thanks!
paesan - Tuesday, September 1, 2009 - link
Wow, does NE really think that anyone will buy the Intel drive at that price. OMG!!! Funny thing, it is in stock and it says limit 1 per customer. LolCList - Tuesday, September 1, 2009 - link
Obviously someone is buying them at that price or they'd lower it. The people who can't wait two or three weeks and are willing to be gouged for these drives are the ones that allow NewEgg to give us low margins on other products while not going out of business :Dravaneli - Tuesday, September 1, 2009 - link
I just decided to buy one and when I opened newegg i couldn't believe my eyes. I hope that is only because they have a few drives left, and once Intel pumps up some stock in the retailers the prices will go back to Intel's retail.Does anyone know what are the production capabilities of Intel's SSD factories? I don't want to wait a whole year until the market saturates.
LazierSaid - Tuesday, September 1, 2009 - link
This article was so good that Newegg doubled their X25M G2 prices overnight.medi01 - Tuesday, September 1, 2009 - link
Yep, very impressive advertisement indeed.HVAC - Tuesday, September 1, 2009 - link
I'd rather have ewoks in the sequels than Jar-jar ...Naccah - Tuesday, September 1, 2009 - link
Newegg's prices on all the Intel SSDs skyrocketed. The X-25 G2s are $499 now. Is this price a reflection of the high demand or did Intel change the price again?