Solid state drive buyer's guide,Help you find a best SSD.

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• Solid State Drive
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• Buyer's Guide
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By:www.bestsolidstatedrive.org

2. Content:
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By:www.bestsolidstatedrive.org .......................................................................................................1
Content: ............................................................................................................................................2
MLC vs SLC: Which flash SSD is right for you?...................................................................................2
SSD installation tips...........................................................................................................................7
KNOW SSD TRIM ......................................................................................................................11
SSD vs HDD: What's the Difference?...............................................................................................13
MLC vs SLC: Which flash SSD is right for you?
As with any technology, there are trade‐offs, depending on which of the two types of
flash SSD you select. Multi‐level cell (MLC) flash is most common and is often found
in consumer‐grade products such as cameras, phones, USB memory sticks and
portable music players but is also present in some enterprise storage products.

3. The main characteristic of MLC flash is its low price, but it suffers from higher wear
rates and lower write performance compared with single‐level cell (SLC) technology.
SLC is faster and much more reliable ‐‐ but also more expensive ‐‐ and is featured in
the best‐performing storage arrays.
In practice, however, the differences are not quite as clear as you may expect. To see
how this technology is developing, its application and where it is heading, we need
to look at how the two types of flash memory work and how they are sold.
Storage sales discussions are not normally about the trade‐offs of MLC vs SLC, said
Valdis Filks, storage technologies director at research firm Gartner. "This is normally
hidden by implementation," he said. "In other words, it's up to the enclosure
manufacturer of the storage array, and it's the controller that's more important than
the underlying storage technology."
MLC vs SLC head to head
Vendors may prefer not to discuss the differences between the technologies, but
understanding the underlying technology can influence deployment strategies. So,
what are the key differences between MLC and SLC flash SSD?
Sansung 840 use TLC Flash
All flash memory suffers from wear, which occurs because erasing or programming a
cell subjects it to wear due to the voltage applied. Each time this happens, a charge
is trapped in the transistor's gate dielectric and causes a permanent shift in the cell's
characteristics, which, after a number of cycles, manifests as a failed cell.
SLC uses a single cell to store one bit of data. MLC memory is more complex and can
interpret four digital states from a signal stored in a single cell. This makes it denser
for a given area and so cheaper to produce, but it wears out faster.

4. So, an MLC cell is typically rated at 10,000 erase/write cycles, while an SLC cell might
last 10 times that before failing. However, manufacturers of products consisting of
MLC cells can and do have ameliorating technologies and techniques at their
disposal.
According to Andrew Buss, service director at analyst firm Freeform Dynamics,
amelioration techniques used by most vendors include wear‐levelling, which moves
write cycles around the chip so that cells wear evenly; on‐device deduplication,
which reduces the volumes of data written and so lowers wear; redundancy, which
reserves a portion of the device's capacity to replace cells as they fail; and write
optimisation, which stores data writes so they can be made in large chunks to reduce
the number of write operations. The emerging term for MLC products that
incorporate such techniques is enterprise MLC, or eMLC.
Most such techniques are implemented in the device controller ‐‐ the interface
between device and computer ‐‐ with companies such
as SandForce and Intel among the most advanced in implementing such
techniques, according to Buss. And despite the endurance issues related to SSDs,
they remain, say vendors, more reliable than spinning media.
Now we have to take one more technical step and take you right into the heart of
what makes SSDs tick. (OK, they don’t tick per se. With no moving parts, SSDs are
actually completely silent—another advantage over hard drives.) We said previously
that SSDs use NAND flash chips. Within each of these chips are millions of cells.
There are only two types of NAND cells today: single‐layer (SLC) or multi‐layer (MLC).
An SLC cell can hold one data bit, yielding a value of either 0 or 1. An MLC cell can
hold more than one, with today’s technologies generally yielding two bits per cell,
yielding values of 00, 01, 10, or 11. Because you can fit four times as many possible
values in a cell, the data density in MLC chips is higher. This is why MLC drives
inevitably have higher capacities than their SLC cousins.

5.
Vendor market share
STEC, which sells 49.9 percent of all SSDs globally, according to Gartner, was the SSD
product market leader in 2009 (Gartner was unable to break out UK figures).
Fusion‐io, Intel, Texas Memory Systems, Samsung and Sun Microsystems follow with
shares all below 9 percent. All the main storage array vendors include SSDs in their
product offerings, pitching them as Tier 1 or Tier 0 in policy‐managed tiered
storage systems.
Use cases
According to Filks, the implementation determines the technology. So applications
such as high‐speed databases, whose performance is measured in terms of
transactions per second, should be matched to the appropriate technology selected
on the basis of price/performance.
"It's about serving more customers in a given time. That's what SSD vendors talk
about," said Filks.
Despite this, MLC and SLC tend to find themselves used for different applications,
due largely to the four‐fold price difference per gigabyte between them. As we have
seen, MLC can be found in consumer‐grade products but also in the enterprise
where performance, while important, is not the primary consideration.
When used in the same storage system, the two types of SSD can be tiered in the
same way as tiering with spinning media; most storage product vendors include a
form of automated SSD tiering, according to Buss. SLC typically tops the storage tier
tree in financial services organisations, where high‐speed access to large databases is
essential and price is a secondary issue. Buss said he sees future products

6. increasingly integrating and both flash SSD types and spinning media in
performance/cost‐based tiers.
Buss said, "Most enterprise applications will rely on a form of database and so will
need SSDs. An example is content management systems, where an end user is
waiting for things to happen; also Exchange servers, websites, media storage ‐‐ all of
which you can use MLC for. However, you still need to do due diligence and buy
appropriately. There are new solutions coming along to make MLC better."
End‐user Roger Bearpark, assistant head of ICT at the London Borough of Hillingdon,
has installed 520 GB of MLC‐based SSD‐based storage into his Compellent arrays. He
said, "MLC is poorer on endurance and performance but is up to three or four [times]
better on price. We got a phenomenal rate of return on investment by putting small
amounts of active data on SSD, which produced a 13‐fold improvement in access
times."
Futures
According to Filks, SSDs will not replace spinning disks. "Everyone says SSDs will
replace disks ‐‐ maybe in about 15 to 20 years' time ‐‐ but as SSD prices drop, so do
those of disks. And SSD prices will never fall as far as disk because factories can't
make enough. It means only the working data set needs to be on SSD, and that's
about 5 to 15 percent of the total."
However, Filks predicted that SSD could eventually replace tape as a deep archive
technology because it offers similar benefits ‐‐ nonvolatility and zero power usage
when not in use ‐‐ although this will take some 10 to 20 years.
As prices fall and reliability techniques improve, it seems likely that MLC technology's
price advantage will see it stay ahead of SLC for all but the most demanding of
applications, as it remains significantly faster and more robust than spinning media.

7. SSD installation tips
With more organizations opting for a DIY approach when it comes to installing
solid‐state drives, here are a half‐dozen helpful tips to consider when debating
whether to take such an approach with SSD installation in an enterprise
environment.
Determine which applications/workloads benefit most from SSD installation
Latency‐sensitive applications with random‐access patterns benefit the most from
performance‐boosting SSDs, and prime flash candidates include online transaction
processing, email and virtual desktop infrastructure, according to Tony Palmer,
senior lab analyst at Enterprise Strategy Group Inc. in Milford, Mass.
"As organizations virtualize and host more applications on fewer servers, the I/O
workload begins quickly to look much more random, so a small to midsize business
with Exchange, SQL Server, SharePoint and other applications all sitting on one or
two servers might benefit from SSD," Palmer wrote in an email.
Dennis Martin, founder and president of Arvada, Colo.‐based consulting and testing
firm Demartek LLC, said hard disk drives (HDDs) are fine with sequential reads and
writes, whereas SSDs do well with random I/O patterns, including database updates
and online analytical processing. He noted that Demartek tested email servers with
SSDs and found the performance was significantly better than even the best hard
drives could deliver. He said those that take the do‐it‐yourself approach could put an
SSD in an email server either as the boot or the storage drive as long as they buy
good‐quality drives with adequate capacity for all the email.
"I think just about anywhere is a good place for an SSD," added Martin, noting that
he "quite frequently boots a little VMware on [an SSD] and runs it from there."
Gartner Inc.'s principal research analyst Sergis Mushell recommended that IT shops
choose applications or workloads that aren't mission‐critical. He suggested putting
metadata on SSDs to accelerate searches, or running highly read websites or pages
with popular videos on SSDs.
"While you get acceleration, your risk is minimal," Mushell said. "But as soon as
you're getting into the primary storage mode and you're endeavoring into 'do it
yourself,' you could be dealing with environments which could be very highly risky
for you."
Research the major types of SSDs and form factors
One of the limitations of SSDs is the wear‐out factor. Bits in a NAND flash block must
be erased before data can be programmed or written, and the program/erase
process eventually breaks down the oxide layer that traps the electrons, causing

8. NAND flash to wear out.
Wear‐out projections differ for the three main types of NAND flash drives currently
in use in enterprise scenarios ‐‐ single‐level cell (SLC), multi‐level cell (MLC) and
enterprise multi‐level cell (eMLC). The traditionally cited figure is 100,000
program/erase (P/E) cycles (which are also known as "write/erase cycles" or
"endurance cycles") for SLC; about 30,000 for eMLC; and 10,000 or considerably less
for MLC.
Storage and server manufacturers initially favored SLC flash for enterprise use but
began to incorporate less‐expensive MLC and eMLC after drive‐makers found ways
to improve their reliability through smarter algorithms for wear leveling and error
correction, overprovisioning, and other mechanisms of increasing sophistication.
MLC can store two or more bits per cell and affords greater capacity than SLC drives.
"Almost everybody's going MLC today," said Marc Staimer, president of Dragon
Slayer Consulting in Beaverton, Ore. "Very few people go SLC unless you're in the
high‐performance compute space."
More expensive SLC flash might be necessary in high‐write scenarios since it features
better performance, reliability and endurance. Cheaper, slower MLC is generally best
suited for read‐intensive workloads that have limited write needs, such as Web
content hosting, video streaming and booting drives in servers. The middle‐ground
option is eMLC.
"MLC and eMLC are the most cost‐effective, but you have to consider the write cliff,"
Palmer wrote. "If you are deploying only one device, SLC might be a better choice,
although more pricey."
Martin said he is comfortable using consumer‐grade MLC for server boot drives
because the drives don't get a lot of writes. Demartek tends to go with eMLC or SLC
in servers with enterprise application data.
Gartner's Mushell added that the "magic" with solid‐state storage is in the wear
leveling and the data integrity, and with about 100 different providers in the market,
customers need to do a careful evaluation of the product manufacturers.
Several form factor options are available for solid‐state storage, but users will likely
find themselves choosing between SAS‐ and SATA‐based SSDs that fit into HDD slots
or PCI Express (PCIe) flash cards that connect directly to the PCIe bus.
One of the main advantages of directly connected PCIe cards is that they bypass the
traditional storage protocol overhead for lower latency. But, Staimer claimed DIY
users may need greater skill to use PCIe cards than SAS‐based SSDs in the HDD form

9. factor.
Staimer said SSDs in the HDD form factor are "a much less risky play than the PCIe
play because you're connecting to a SAS controller that's already in the system." On
the other hand, users will have lower performance because they're limited by the
SAS controller.
Select the optimal location for solid‐state storage
High‐end arrays from well‐known manufacturers aren't the ideal place to tinker with
SSDs purchased on the open market. That's because uncertified drives could have an
impact on the warranty and possibly even the system operation.
For those that DIY, Staimer advised SSD installation on desktops, laptops and servers,
in that order. "Just a bunch of disks"‐‐ several disks in a chassis that connect to a
server ‐‐ are also good candidates. "Storage [arrays], not so much. Anything that has
a brand name it, you'll void the warranty if you open it up."
Options for sharing embedded‐server SSDs and PCIe flash cards between multiple
servers include Sanbolic Inc.'s Melio software and QLogic Corp.'s Mt. Rainier host bus
adapter (HBA) technology, which is due in 2013. But, such products tack on costs for
DIYers.
Don't rule out flash cache
When it comes to installing SSDs, DIYers may be inclined to favor SSDs for primary
storage, but Martin said they shouldn't rule out flash cache. He noted that caching is
a simple addition that requires no application or storage changes and provides a
significant performance boost.
Caching does, however, require software sold through an SSD vendor, storage/server
vendor or a separate software company. Options include server‐based products
from Fusion‐io Inc., LSI Corp., OCZ Technology Group Inc., SanDisk Corp. and VeloBit
Inc.; and software from EMC Corp., NetApp Inc. and smaller vendors. Also, QLogic's
upcoming Mt. Rainier HBA technology aims to allow sharing of cached data among
multiple servers equipped with its PCIe cards or SAS‐based SSDs in environments
that use SAN storage.
Caching software typically determines the most frequently accessed data and shifts a
copy to the flash cache. Flash cache products tend to use PCIe cards connected
directly to the CPU and system memory rather than SAS‐ or SATA‐based SSDs.
Server‐based flash cache options reduce the latency associated with the network
hop.
Check warranty and support agreements with your server/storage vendor
Vendors of name‐brand storage arrays and servers may have tested and certified

10. their products with only select SSDs and PCIe cards, so enterprise IT shops need to
check support contracts and warranties before installing SSDs to see if drives
purchased on the open market will affect their agreements.
"If you're talking about a big name‐brand storage system, you can't just go and swap
out the drives. You need to get the right drive," Martin said. But the IT shop may be
able to buy the drives from a secondary source rather than from the server or
storage vendor.
Staimer said potential DIYers need to be careful. "Many server vendors will say, 'If it
doesn't come from us, your warranty will be voided,' and it will invalidate your
service contracts, too," he said. "They'll fix [a problem], but it's coming out of your
pocket completely."
Buy spares
Drives fail, whether they're HDDs, SSDs or PCIe flash cards, so IT shops that take the
DIY approach need to buy spares. And because the SSDs and PCIe flash cards are
more expensive than HDDs, they might want to check a number of data points to
help determine the number of spares to keep on hand.
Martin advised looking at the lengths of warranties with the expectation that
enterprise SSDs carry longer guarantees than consumer‐grade products. He further
suggested looking for manufacturer‐supplied figures such as terabytes written
(TBW).
"Although the SSD vendors provide that data, very few end users have done that
calculation on their hard drives, so they don't really have any point of comparison,"
Martin said. "With hard drives, you don't really think about terabytes written per day,
so most people don't know what a good number would be."
TBW represents the maximum number of terabytes that a host can write to an SSD
using a specified workload and application class (client or enterprise). The JEDEC
Solid State Technology Association, formerly known as the Joint Electron Devices
Engineering Council (JEDEC), offers guidelines for determining TBW, which is also
known as an "endurance rating," to allow comparison between different SSDs and
vendors through a standard mechanism.

11. KNOW SSD TRIM
Now that solid‐state drives (SSDs) are becoming an affordable alternative to hard
drives, certain terms are being used quite often. One of these terms is "TRIM
support." To understand what TRIM support is, you first need to understand how
solid‐state drives work. SSDs use NAND flash memory to store and transfer
information. This flash memory is created up of small "pages" and groups of pages
are called "blocks." When you tell your computer to delete a page on the solid‐state
drive the page isn't actually deleted ‐ it is merely marked for deletion. This is because
data can only be deleted in blocks. You cannot delete individual pages on an SSD.
Later on, when you tell your computer that you need the space, the pages marked
for deletion are grouped into a block and the whole block is wiped clean. This
process slows down the solid‐state drive when it is writing.
Let us explain in a different way.
Imagine, if you will, that you have a stack of blank papers on your desk at work. Each
workday you keep the papers with important information on them, but get rid of the
unnecessary papers, like the one you doodled on during a boring meeting, by putting
them in the "To Be Recycled" tray on your desk. It's not worth going all the way
down to the recycling center for a few sheets of paper, so you wait until you have a
stack that is worth the travel time.
Eventually, you run out of blank paper. Since you have a project due that day, it is
now time to use the paper from the "To Be Recycled" tray. You take out your eraser
and get to work. Erasing takes a lot of effort, so you decide to only clean up a portion
of the stack to tide you over for a while. Eventually you will run out of paper again
and you'll have to erase another portion, but you plan on crossing that bridge when
you come to it.
That is why solid‐state drives slow down while writing after prolonged use. They
have to clean the files marked for deletion before they can be written on, and
erasing takes time. This can cause serious delays, depending on how much data
you're trying to save and how much needs to be deleted. Luckily, TRIM alleviates this
problem and is supported on many of the SSDs and operating systems made today.
A TRIM command enables your operating system to find the marked pages before
you need them and wipe them clean. Cleaning these data pages beforehand saves
you time when you need to write on the data pages again. It's like you have your
own recycling guy next to your desk, recycling the pieces of paper as they come.
In order to work correctly, TRIM has to be supported by both the solid‐state drive
and the operating system you are using. When both the OS and the SSD support
TRIM individual pages can be cleaned and your solid‐state drive will be informed that

12. the pages are now blank and can be written on. This kind of cleaning and
communication is essential to keep your drive performing to the best of its abilities.
SSDs such as the OCZ Vertex 2, the OCZ Agility 2 and the Corsair Force, as well as
most of the other storage devices on our solid‐state drive review, all feature native
TRIM support. TRIM support is essential for an SSD to run the way it should. To avoid
slow writing times, and to save yourself from frustration, make sure that the
solid‐state drive you are buying includes TRIM support.

13. SSD vs HDD: What's the Difference?
Up until this year, PC buyers had very little choice for what kind of primary storage
they got with their laptop, nettop, netbook, or desktop. If you bought a netbook or
ultraportable, you likely had a solid‐state drive (SSD) as the primary drive (C: on
Windows, Macintosh HD on a Mac). Everything other desktop or laptop form factor
had a hard disk drive (HDD). Now, you can configure your system with either an HDD,
SSD, or in some cases both. But how do you choose? We explain the differences
between SSDs and HDDs, and walk you through the advantages and disadvantage of
both to help you come to your decision.
What is a HDD, What is a SSD? The traditional spinning hard drive (HDD) is the basic
nonvolatile storage on a computer. That is, it doesn't "go away" like the data on the
system memory when you turn the system off. Hard drives are essentially metal
platters with a magnetic coating. That coating stores your data, whether that data
consists weather reports from the last century, a high‐definition copy of the Star
Wars trilogy, or your digital music collection. A read/write head on an arm accesses
the data while the platters are spinning in a hard drive enclosure.
An SSD does much the same job functionally (saving your data while the system is off,
booting your system, etc.) as an HDD, but instead of a magnetic coating on top of
platters, the data is stored on interconnected flash memory chips that retain the
data even when there's no power present. The chips can either be permanently
installed on the system's motherboard (like on some small laptops and netbooks), on
a PCI/PCIe card (in some high‐end workstations), or in a box that's sized, shaped, and
wired to slot in for a laptop or desktop's hard drive (common on everything else).
These flash memory chips differ from the flash memory in USB thumb drives in the
type and speed of the memory. That's the subject of a totally separate technical
treatise, but suffice it to say that the flash memory in SSDs is faster and more reliable
than the flash memory in USB thumb drives. SSDs are consequently more expensive
than USB thumb drives for the same capacities.
Hard drive technology is relatively ancient (in terms of computer history). There are
well known pictures of the infamous IBM 350 RAMAC hard drive from 1956 that
used 50 24‐inch wide platters to hold a whopping 3.75MB of storage space. This, of
course, is the size of an average 128Kbps MP3 file, in the physical space that could
hold two commercial refrigerators. The IBM 350 was only used by government and
industrial users, and was obsolete by 1969. Ain't progress wonderful? The PC hard
drive form factor standardized in the early 1980s with the desktop‐class 5.25‐inch
form factor, with 3.5‐inch desktop and 2.5‐inch notebook‐class drives coming soon
thereafter. The internal cable interface has changed from Serial to IDE to SCSI to
SATA over the years, but it essentially does the same thing: connects the hard drive
to the PC's motherboard so your data can be processed. Today's 2.5‐ and 3.5‐inch
drives use SATA interfaces almost exclusively (at least on most PCs and Macs).
Capacities have grown from multiple megabytes to multiple terabytes, an increase of
millions fold. Current 3.5‐inch HDDs max out at 4TB, with 2.5‐inch drives at 2TB max.

14. The SSD has a much more recent history. There was always an infatuation with
non‐moving storage from the beginning of personal computing, with technologies
like bubble memory flashing (pun intended) and dying in the 1970s and '80s. Current
flash memory is the logical extension of the same idea. The flash memory chips store
your data and don't require constant power to retain that data. The first primary
drives that we know as SSDs started during the rise of netbooks in the late 2000s. In
2007, the OLPC XO‐1 used a 1GB SSD, and the Asus Eee PC 700 series used a 2GB SSD
as primary storage. The SSD chips on low end Eee PC units and the XO‐1 were
permanently soldered to the motherboard. As netbooks and other ultraportables
became more capable, the SSD capacities rose, and eventually standardized on the
2.5‐inch notebook form factor. This way, you could pop a 2.5‐inch hard drive out of
your laptop or desktop and replace it easily with a SSD. Other form factors emerged,
like the DIMM‐like SSDs in the Apple MacBook Air, but today many SSDs are built
into the 2.5‐inch form factor. The 2.5‐inch SSD capacity tops out at 1TB currently, but
they're undoubtedly going to grow as time goes by.
Advantages/Disadvantages
Both SSDs and HDDs do the same job: They boot your system, store your
applications, and store your personal files. But each type of storage has its own
unique feature set. The question is what's the difference, and why would a user get
one over the other? We break it down:
Price: To put it bluntly, SSDs are frakking expensive in terms of dollar per GB. For the
same capacity and form factor 1TB internal 2.5‐inch drive, you'll be paying about
$100 for a HDD, but as of this writing, you'll be paying a whopping $900 for an SSD.
That translates into ten‐cents‐per‐GB for the HDD and ninety cents per GB for the
SSD. Other capacities are slightly more affordable (250 to 256GB: $250 SSD, $70
HDD), but you get the idea. Since HDDs are older, more established technologies,
they will remain to be less expensive for the near future. Those extra hundreds may
push your system price over budget.
Maximum and Common Capacity: As seen above, SSD units top out at 1TB, but those
are very rare and expensive. You're more likely to find 128GB to 500GB units as
primary drives in systems. You'd be hard pressed to find a 128GB HDD in a PC these
days, as 250 or even 500GB is considered a "base" system in 2012. Multimedia users
will require even more, with 1TB to 4TB drives as common in high‐end systems.
Basically, the more storage capacity, the more stuff (photos, music, videos, etc) you
can hold on your PC. While the (Internet) cloud may be a good place to share these
files between your phone, tablet, and PC, local storage is less expensive, and you
only have to buy it once.
Speed: This is where SSDs shine. A SSD‐equipped PC will boot in seconds, certainly
under a minute. A hard drive requires time to speed up to operating specs, and will
continue to be slower than a SSD during normal operation. A PC or Mac with an SSD
boots faster, launches apps faster, and has higher overall performance. Witness the
higher PCMark scores on laptops and desktops with SSD drives, plus the much higher
scores and transfer times for external SSDs vs. HDDs. Whether it's for fun, school, or
business, the extra speed may be the difference between finishing on time or failing.

15. Fragmentation: Because of their spiral‐like recording surfaces, HDD surfaces work
best with larger files that are laid down in contiguous blocks. That way, the drive
head can start and end its read in one continuous motion. When hard drives start to
fill up, large files can become scattered around the disk platter, which is otherwise
known as fragmentation. While read/write algorithms have improved where the
effect in minimized, the fact of the matter is that HDDs can become fragmented,
while SSDs don't care where the data is stored on its chips, since there's no physical
read head. SSDs are inherently faster.
Durability: An SSD has no moving parts, so it is more likely to keep your data safe in
the event that you drop your laptop bag or your system is shaken about by an
earthquake while it's operating. Most hard drives park their read/write heads when
the system is off, but they are flying over the drive platter at hundreds of miles an
hour when they are in operation. Besides, even parking brakes have limits. If you're
rough on your equipment, a SSD is recommended.
Availability: Even taking the flooding in Thailand in late 2011 (a major HDD
manufacturing center) into account, hard drives are simply more plentiful. Look at
the product lists from Western Digital, Toshiba, Seagate, Samsung, and Hitachi, and
you'll see many more HDD model numbers than SSDs. For PCs and Macs, HDDs won't
be going away, at least for the next couple of years. You'll also see many more HDD
choices than SSDs from different manufacturers for the same capacities.
Form Factors: Because HDDs rely on spinning platters, there is a limit to how small
they can be manufactured. There was an initiative to make smaller 1.8‐inch spinning
hard drives, but that's stalled at about 320GB, since the MP3 player and smartphone
manufacturers have settled on flash memory for their primary storage. SSDs have no
such limitation, so they can continue to shrink as time goes on. SSDs are available in
2.5‐inch laptop drive sized boxes, but that's only for convenience, as stated above.
As laptops become slimmer and tablets take over as primary web surfing platforms,
you'll start to see the adoption of SSDs skyrocket.
Noise: Even the quietest HDD will emit a bit of noise when it is in use from the drive
spinning or the read arm moving back and forth, particularly if it's in a system that's
been banged about or in an all‐metal system where it's been shoddily installed.
Faster hard drives will make more noise than slower ones. SSDs make virtually no
noise at all, since they're non‐mechanical.
Overall: HDDs win on price, capacity, and availability. SSDs work best if speed,
ruggedness, form factor, noise, or fragmentation (technically part of speed) are
important factors to you. If it weren't for the price and capacity issues, SSDs would
be the winner hands down.
As far as longevity goes, while it is true that SSDs wear out over time (each cell in a
flash memory bank has a limited number of times it can be written and erased),
thanks to TRIM technology built into SSDs that dynamically optimizes these
read/write cycles, you're more likely to discard the system for obsolescence before
you start running into read/write errors. The possible exception are high‐end
multimedia users like video editors who read and write data constantly, but those
users will need the larger capacities of hard drives anyway. Hard drives will

16. eventually wear out from constant use as well, since they use physical recording
methods. Longevity is a wash when it's separated from travel and ruggedness
concerns.