SSD Buyer's Guide

Newbie SSD Buyer's Guide

Introduction

Everyone wants to have the sleekest hardware money can buy. Well almost everyone. As always money buys speed, and that works out exponentially in favor of spending tones to get that edge over mainstream performance. Now there is a way where investing on your slowest component in your computer can work wonders. You will be amazed at how well your computer responds to your every click.

This magical piece of hardware is the Solid State Drive. Mass storage being one of the slowest component as Hard Disk Drives continue to use mechanical parts which in turn make storing and retrieving data a comparatively slow process when other, much faster components such as RAM and the CPU, have to wait for the HDD to complete its work. This is because the data is stored on disks (or platters) which have to rotate on a spindle with the help of a motor, and a head/multiple heads move over these platters retrieves the relevant data. Very complicated, don’t you think?

But now “Solid State Drives are IN DA HOUSE”. Not exactly a magical new device. It has been available from the past 8-10 years. But recently, from the past 1-2 years a revolution has occurred in terms of how fast these things work when compared to a regular HDD. Seek times are about a 100 times faster and the read and write speeds are 2 to 3 times faster than traditional HDD’s. SSD’s use NAND Flash Memory chips. You will find multiple NAND chips (usually multiples of 8/16GB) on a SSD.

Enough of that nonsense. Now let’s get down to what matters: what to look for, when it comes to buying a spanking new SSD.

Space:Price


Nothing new when it comes to storage, you would like to get as much space money can buy. But when 1GB of SSD space costs as much as Rs.150 to 200, you might want to think a little more. SSD’s are available with capacities ranging from 32GB to 512GB. But I would say that the current sweet spot is between 40GB and 128GB. This gives enough space for your primary partition and programs that you would usually use. 128GB would help if you are a gamer.

Current prices are about Rs. 4000 for a 32GB drive and go all the way up to 60K for a 512GB drive!!!

NAND Flash Memory Types

There are two types of NAND Flash memory being used on SSD’s

• SLC: (Single Level Cell) which stores one bit per cell. This is the faster and the more expensive type
• MLC: (Multi Level Cell) stores 2 bits per cell. It’s slow compared to SLC and cheaper to manufacture. But less reliable as each cell can be over written only about 10,000 times. Where as a SLC can do about 100k writes.

But most manufacturers pack SSD’s with MLC type NAND. Although they are not as reliable as SLC, they use smart memory controllers, which spread the write cycles evenly over all the available cells, so as to get the maximum life from each cell. Current drives using MLC usually come with 100,000 Hrs MTBF(Mean Time before Failure) which accounts to over 10 Years of continuous usage. This is just a claim that manufacturers make, I wouldn't put my money on it. Since most drives are made from MLC flash I would suggest you go for a MLC SSD with a warranty of at least 3 yrs to stay safe.

Memory Controllers


The Memory Controller is your SSD’s most crucial component. This is what matters when it comes to how fast your drive works, and its reliability. So choose wisely. Most current generation memory controllers can manage Read speeds of unto 280MBps and write speeds up to 270 MBps. I would suggest you look of for one these controllers, namely: Indilinx Barefoot, Sandforce 1200/1500, JMicron JMF612 or Marvell. They are the faster when compared to the others and the latter supports SATA III and has the best read speeds when compared to the rest. Before you do make a purchase I recommend reading a few reviews of the product, as the innovation in SSD performance in focused on these controllers and you can find newer versions of these controllers almost every couple of months.

SATA II or SATA III

Only a few Sata III SSD’s are available right now (Crucial which used the Marvell Sata III controllers). These drives boast speeds of up to 380MBps. But their write speeds are not up to par when compared to some of the other SATA II SSD’s. SSD’s which have SATA II controllers have kind of hit the limit with a peak read performance of about 280MBps.If you have a sata III motherboard and you feel that 280MBps is not going to cut it, I suggest you wait a little while longer for better performing drives than the Crucial/Marvell SSD’s as the write performance is much slower than the other Sata II drives. It is still a respectable speed though, 150MBps is still no slouch. But when you see sata II drives which are able to reach 270MBps, you might think I have a point.

TRIM Support


Almost all new controllers come with TRIM support. In other cases TRIM is available via firmware updates.

Hmm what is TRIM? :To keep it simple TRIM command allows an operating system to inform the SSD, which data blocks, such as those belonging to a deleted file or affected by a format command, are no longer considered in use and can be wiped internally. TRIM enables the SSD to handle garbage collection overhead, in advance, that would otherwise significantly slow down future write operations to the involved blocks.

Without TRIM the drive performance will degrade over time. Trim is an Operating System feature and is supported by only the following Operating Systems:

• Windows 7
• Windows Server 2008 R2
• Linux 2.6.33
• Open Solaris
• FreeBSD 8.1

Conclusion

These are some of the things to keep in mind while buying a SSD for now. I hope it helps guys like me who was wondering what matters when it comes to buying a SSD. This technology is evolving constantly, with new innovations coming in every month. But as of now, if you carefully consider all the above mentioned points, you are good to go the SSD way.