Solid state disks (SSDs) Q&A

JDtech · 07-03-2010, 07:06 PM

Q: The rpm ratings of magnetic hard drives are what I use to determine how fast they are. If I buy an SSD, what should I pay attention to when it comes to speed?

A: First of all, even the slowest of contemporary SSDs will typically read and write data faster than mainstream hard disks, which rely upon rapidly spinning platters with magnetic surfaces. As you probably know, the speed at which those platters spin determines, in large part, how quickly data can be read from them and written to them. That rating is expressed in revolutions per minute (rpm), and today desktop drives that spin at 5400 or 7200 rpm are the norm, with some 10,000 rpm drives preferred by power users.

SSDs are made up of memory chips. There's nothing that spins, so rpm ratings are history. Instead, as with conventional system memory, the rates at which data can be written to and read from an SSD's memory chips are expressed in megabytes per second, usually abbreviated as MB/s. Look at the fine print on an SSD's packaging or online, and you should see two MB/s ratings: one for reading data from the disk and one for writing data to the disk.

Ordinarily SSDs can read data from their internal flash memory faster than they can write data to it. Today, read speeds are in the range of 135 to 260 MB/s. Write speeds range roughly from 35 to 190 MB/s. As you can see, the difference between the slowest SSDs and the fastest can be significant - at least on paper. In practice, however, you're likely to be so impressed with the speed difference of just about any SSD over your existing hard drive that you'll be happy even with an SSD that's slow relative to others.

Q: Are all SSDs equally reliable?

A: Theoretically SSDs should be very reliable, given that they contain no moving parts - unlike traditional drives, which contain delicate read-write heads floating just a hair's breadth above rapidly rotating platters. However, early reviews of SSDs often focused on the fact that the chips in solid state disks could "wear out" over time, as the internal chips' life span was reduced with repeated writing of data that occurs with hard drives.

Manufacturers responded by incorporating "wear leveling" technology, which ensured data was written evenly across all of the chips within a drive rather than just a few. Wear-leveling or not, reports of SSDs wearing out from overuse have been virtually nonexistent thus far. And recent studies of expected SSD longevity using various constant writing scenarios peg life expectancy of today's SSDs anywhere from 12.9 to over 50 years. If those estimates hold up, you're almost certain to outgrow the capacity of any SSD you buy today long before you wear it out.

Q: Why are some SSDs faster than others?

A: A primary differentiator of SSDs today lies in the controller technology, which handles data protection as well as writing, erasing, and wear leveling. In short, an SSD's controller is responsible for a great deal of critical activity, and some controllers simply perform better - and faster - than others. Many original SSD users complained of drives that would hang or pause temporarily or simply couldn't be counted on to run smoothly for an entire computing session - issues that were blamed squarely on controllers.

That's why you'll see many SSD manufacturers trumpeting the virtues of the controller technology they employ as much as any other feature of the drive. And not all manufacturers make their own controllers. In fact, most do not. Intel's SSD controller technology is used by several other SSD vendors. Along with new controllers from Samsung, Intel's are widely considered among the best.

Q: I'm interested in upgrading my notebook with an SSD. Can I expect to see better battery life after the upgrade?

A: The subject of power consumption and SSDs has been hotly debated in technology circles, primarily because some tests have shown that SSDs can give notebook users an extra 30 minutes or so of battery life per charge, while others concluded that SSDs offer no energy savings or even perform worse in this department than traditional hard drives. The different results typically stem from multiple factors: whether drives and SSDs were in a constantly active state, which SSDs were tested, and which notebooks.

For those less concerned with benchmarks than real-world results, however, the consensus seems to be that at the worst, you'll notice no appreciable reduction in battery life by using a modern SSD, and the speed gain you achieve by using an SSD will more than make up for any degradation of battery life that you might experience.

kellycat · 07-03-2010, 09:17 PM

A very useful post. When do you think we will see comparable cost/MB between SSDs and conventional rotating platter HDs?

JDtech · 07-03-2010, 09:30 PM

Quote:

Originally Posted by kellycat

A very useful post. When do you think we will see comparable cost/MB between SSDs and conventional rotating platter HDs?

Hard to say. I would have thought that prices of SSDs would have come down faster than they have. But they are now beginning to come down. There are a lot of players/manufacturers in this market, and the competition--combined with the expanding market--is bound to drive down prices.

Still, models that are both highly rated and offer decent capacity, such as Intel's 160GB model, are still around $400, which is a lot to pay for a drive. However, it wasn't long ago that you could pay $125 more for that model. And it has to be said that an SSD is one of those upgrades that will make you say "I'll never go back" to a traditional drive.

kellycat · 07-03-2010, 10:16 PM

It is a shame that SSDs seem to remain a pricey option primarily for laptops and seldom, if ever, offered in the standard configuration of desktop computers by manufacturers like HP or Apple. Now that I think of it, I don't recall seeing anything other than 3rd party SSDs being available. Are there any major manufacturers of computer systems out there that are offering SSDs in their Desktop configurations?

JDtech · 07-03-2010, 10:20 PM

Quote:

Originally Posted by kellycat

Are there any major manufacturers of computer systems out there that are offering SSDs in their Desktop configurations?

I'm sure there are. I'm running an SSD as the boot drive (and primary application storage drive) of most of my computers. I find 80, 120, or 160GB--the typical size of SSDs--to be sufficient for boot drives. To store data files, I used a traditional drive of 1 TB or so.

Jon Foster · 07-04-2010, 01:43 AM

People ask about SSD's in the store all the time. We don't carry then as a standard item but will special order them. When people see the price difference between the SSD's and the huge 1TB, 2TB or even the 4TB drives they all seem to put the SSD's out of their mind.

Jon.

JDtech · 07-04-2010, 07:40 AM

Well, the 80 GB Intel model is down to just over $200, which is doable for many. Couple that with a 1 TB drive, now down to under $100, and you're looking at the best of bost worlds: very fast boot and application run times and massive storage for files, music, downloads, etc.

Jon Foster · 07-04-2010, 02:00 PM

I'll have to check the price on the 1TB SATA drives at the store but I'm pretty sure we sell them for under $80.00.

On a side note, IDE drives are much harder to get now and the prices are going up daily.

Jon.

07-03-2010, 07:06 PM	#1
JDtech Senior Member Join Date: Feb 2009 Posts: 308 Blog Entries: 1	Solid state disks (SSDs) Q&A Q: The rpm ratings of magnetic hard drives are what I use to determine how fast they are. If I buy an SSD, what should I pay attention to when it comes to speed? A: First of all, even the slowest of contemporary SSDs will typically read and write data faster than mainstream hard disks, which rely upon rapidly spinning platters with magnetic surfaces. As you probably know, the speed at which those platters spin determines, in large part, how quickly data can be read from them and written to them. That rating is expressed in revolutions per minute (rpm), and today desktop drives that spin at 5400 or 7200 rpm are the norm, with some 10,000 rpm drives preferred by power users. SSDs are made up of memory chips. There's nothing that spins, so rpm ratings are history. Instead, as with conventional system memory, the rates at which data can be written to and read from an SSD's memory chips are expressed in megabytes per second, usually abbreviated as MB/s. Look at the fine print on an SSD's packaging or online, and you should see two MB/s ratings: one for reading data from the disk and one for writing data to the disk. Ordinarily SSDs can read data from their internal flash memory faster than they can write data to it. Today, read speeds are in the range of 135 to 260 MB/s. Write speeds range roughly from 35 to 190 MB/s. As you can see, the difference between the slowest SSDs and the fastest can be significant - at least on paper. In practice, however, you're likely to be so impressed with the speed difference of just about any SSD over your existing hard drive that you'll be happy even with an SSD that's slow relative to others. Q: Are all SSDs equally reliable? A: Theoretically SSDs should be very reliable, given that they contain no moving parts - unlike traditional drives, which contain delicate read-write heads floating just a hair's breadth above rapidly rotating platters. However, early reviews of SSDs often focused on the fact that the chips in solid state disks could "wear out" over time, as the internal chips' life span was reduced with repeated writing of data that occurs with hard drives. Manufacturers responded by incorporating "wear leveling" technology, which ensured data was written evenly across all of the chips within a drive rather than just a few. Wear-leveling or not, reports of SSDs wearing out from overuse have been virtually nonexistent thus far. And recent studies of expected SSD longevity using various constant writing scenarios peg life expectancy of today's SSDs anywhere from 12.9 to over 50 years. If those estimates hold up, you're almost certain to outgrow the capacity of any SSD you buy today long before you wear it out. Q: Why are some SSDs faster than others? A: A primary differentiator of SSDs today lies in the controller technology, which handles data protection as well as writing, erasing, and wear leveling. In short, an SSD's controller is responsible for a great deal of critical activity, and some controllers simply perform better - and faster - than others. Many original SSD users complained of drives that would hang or pause temporarily or simply couldn't be counted on to run smoothly for an entire computing session - issues that were blamed squarely on controllers. That's why you'll see many SSD manufacturers trumpeting the virtues of the controller technology they employ as much as any other feature of the drive. And not all manufacturers make their own controllers. In fact, most do not. Intel's SSD controller technology is used by several other SSD vendors. Along with new controllers from Samsung, Intel's are widely considered among the best. Q: I'm interested in upgrading my notebook with an SSD. Can I expect to see better battery life after the upgrade? A: The subject of power consumption and SSDs has been hotly debated in technology circles, primarily because some tests have shown that SSDs can give notebook users an extra 30 minutes or so of battery life per charge, while others concluded that SSDs offer no energy savings or even perform worse in this department than traditional hard drives. The different results typically stem from multiple factors: whether drives and SSDs were in a constantly active state, which SSDs were tested, and which notebooks. For those less concerned with benchmarks than real-world results, however, the consensus seems to be that at the worst, you'll notice no appreciable reduction in battery life by using a modern SSD, and the speed gain you achieve by using an SSD will more than make up for any degradation of battery life that you might experience. __________________ Members don't see ads in threads. Register your free account today and become a member on Tech Today Online, gaining access to posting privileges, contests, free plug-ins and other downloads, unlimited online storage for your photographs, reviews, free marketplace listings, and much more.

07-03-2010, 09:17 PM	#2
kellycat Junior Member Join Date: Jul 2010 Location: Denver Posts: 23	A very useful post. When do you think we will see comparable cost/MB between SSDs and conventional rotating platter HDs? __________________ Kellycat

07-03-2010, 10:16 PM	#4
kellycat Junior Member Join Date: Jul 2010 Location: Denver Posts: 23	It is a shame that SSDs seem to remain a pricey option primarily for laptops and seldom, if ever, offered in the standard configuration of desktop computers by manufacturers like HP or Apple. Now that I think of it, I don't recall seeing anything other than 3rd party SSDs being available. Are there any major manufacturers of computer systems out there that are offering SSDs in their Desktop configurations? __________________ Kellycat

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07-04-2010, 01:43 AM	#6
Jon Foster Senior Member Join Date: Jul 2010 Location: White Lake, MI Posts: 149	People ask about SSD's in the store all the time. We don't carry then as a standard item but will special order them. When people see the price difference between the SSD's and the huge 1TB, 2TB or even the 4TB drives they all seem to put the SSD's out of their mind. Jon.

07-04-2010, 07:40 AM	#7
JDtech Senior Member Join Date: Feb 2009 Posts: 308 Blog Entries: 1	Well, the 80 GB Intel model is down to just over $200, which is doable for many. Couple that with a 1 TB drive, now down to under $100, and you're looking at the best of bost worlds: very fast boot and application run times and massive storage for files, music, downloads, etc.

07-04-2010, 02:00 PM	#8
Jon Foster Senior Member Join Date: Jul 2010 Location: White Lake, MI Posts: 149	I'll have to check the price on the 1TB SATA drives at the store but I'm pretty sure we sell them for under $80.00. On a side note, IDE drives are much harder to get now and the prices are going up daily. Jon.