Anandtech - The SSD Relapse: Understanding and Choosing the Best SSD

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The SSD Relapse: Understanding and Choosing the Best SSD

One Tough Act to Follow

What have I gotten myself into? The SSD Anthology I wrote back in March was read over 2 million times. Microsoft linked it, Wikipedia linked it, my esteemed colleagues in the press linked it, Linus freakin Torvalds linked it.

The Anthology took me six months to piece together; I wrote and re-wrote parts of that article more times than I'd care to admit. And today I'm charged with the task of producing its successor. I can't do it.

The article that started all of this was the Intel X25-M review. Intel gave me gold with that drive; the article wrote itself, the X25-M was awesome, everything else in the market was crap.

The Anthology all began with a spark: the SSD performance degradation issue. It took a while to put together, but the concept and the article were handed to me on a silver platter: just use an SSD for a while and you’ll spot the issue. I just had to do the testing and writing.

But today, as I write this, the words just aren't coming to me. The material is all there, but it just seems so mature and at the same time, so clouded and so done. We've found the undiscovered country, we've left no stone unturned, everyone knows how these things work - now SSD reviews join the rest as a bunch of graphs and analysis, hopefully with witty commentary in between.

It's a daunting, no, deflating task to write what I view as the third part in this trilogy of articles. JMicron is all but gone from the market for now, Indilinx came and improved (a lot) and TRIM is nearly upon us. Plus, we all know how trilogies turn out. Here's hoping that this one doesn't have Ewoks in it .....
 
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Very nice article. Intel is still king, whilst Indilinx drives are a close second.

And we can finally put to bed the debate on how much disk space there is. 80GB=80GB actual physical space.

Intel's 80GB X25-M has 80GB of NAND flash on it. That's 85,899,345,920 bytes or 80 x 1024^3 bytes (1024 bytes in a kilobyte x 1024 kilobytes in a megabyte x 1024 megabytes in a gigabyte x 80 gigabytes).

Hard drive makers however assume that 80GB means 80,000,000,000 bytes, since they use the definition of 1GB = 1,000,000,000 bytes. SSD vendors thus use the same definition. Now 80,000,000,000 bytes actually equals 74.5GB, so that's all the space you get to use on the drive.

How much space is there really on the drive? 80GB. How much space does Windows let you use? 74.5GB. What happens to the remaining 5.5GB? It's used by the drive's controller as spare area.

Intel’s controller is dynamic, it uses the entire drive as spare area until you’ve written every LBA once. Then it relies on the remaining 7.5% of non-user-space as its scratch pad. That’s why its new, out of box, performance is so good.
 
Despite the length of the article (27 pages !) it's a superb, must read, I strongly recommend anyone considering buying an SSD read this article before they make a decision on the drive they want to buy.
 
Still reading..... its good though :)

just finished and I have to say this is an excellent read.

And you must read it if you intend to purchase an SSD in the coming months, it is missing only one thing, OSX benchmarks on each SSD.
 
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