From some reviews, SSD is obviously much faster than HDD.

For example, SSD can largely reduce the boot time:

http://www.kitguru.net/components/ssd-drives/zardon/kingston-ssdnow-v100-128gb-ssd-review/

But SSD’s lifespan is still a big issue…

Does anybody know what the average life expectancy of SSD?

I found that there are several technologies of controller to optimize SSD such as wear leveling, garbage collection and Trim. Can these help to prolong SSD’s life?

Let's quickly do the math again. If you have a 100GB drive and you write 7GB per day you'll program every MLC NAND cell in the drive in just over 14 days—that's one cycle out of three thousand. Outside of SandForce controllers, most SSD controllers will have a write amplification factor greater than 1 in any workload. If we assume a constant write amplification of 20x (and perfect wear leveling) we're still talking about a useful NAND lifespan of almost 6 years. In practice, write amplification for desktop workloads is significantly lower than that.

Courtesy of Anandtech.

The wear-leveling algorithm allows the lifetime calculation to be simply described as the product of the SSD capacity

and the P/E cycle endurance of the flash memory divided by the usage per day. Additional factors such as percent

utilization can be used as a safety net to indicate when wear out is imminent, and a capacitor rate factor is added to

the equation to indicate the written overhead accompanying the data. The capacity rate factor, as described earlier, is

constant for the sequentially written usage strategy, but can vary when alternative write strategies are used, causing

the overhead to vary in size.

Parameters:

- NAND flash P/E cycle endurance

SLC 100,000 cycles, MLC 10,000 cycles

- NAND flash P/E utilization

The allowable amount of P/E utilization before flash memory is considered worn out – 95%

- SSD capacity

Total capacity of the SSD

- Capacity rate factor – The amount of written overhead accompanying the data

Sequential write has a constant value of 1.1

Mixed written data has a value that varies depending on the percent mixture of sequential and random written data

(SSD-Capacity(GB))(P/E)(Percent Utilization)

Lifetime (years) = ---------------------------------

(Usage/Day)(Capaciy Rate)(365days/year)

http://www.imation.com/PageFiles/83/SSD-Reliability-Lifetime-White-Paper.pdf

Modern SSDs have an MTBF (Mean Time Between Failures) of about 1.5 Millions hours of continuous operation.

That means if your computer is on 24 hours a day 7 days a week and the disk is being read constantly, it will last for:

171 years.

Of course, it will last considerably longer than that if is not running at 100% all the time.

So figure for a normal user, about 400 years.

But by then, you'll probably want a new computer anyway

Modern SSDs have an MTBF (Mean Time Between Failures) of about 1.5 Millions hours of continuous operation.

That means if your computer is on 24 hours a day 7 days a week and the disk is being read constantly, it will last for:

171 years.

Of course, it will last considerably longer than that if is not running at 100% all the time.

So figure for a normal user, about 400 years.

But by then, you'll probably want a new computer anyway

Ummh, no. That 1,5M rating may be true in the sense that's how long it would last before it was no good; but that does not mean how long cells in it are still available for writing. As posted elsewhere in this thread it's number of writes that matter not how long it's on. An SSD cell can only be written to x number of times before it will not be able to be overwritten again; note that the contents are still available for read at a minimum of 1 year after that point.

As a side note Seagate lists its Constellation ES drives for 1,2 M hours MTBF.

Ummh, no.

Was about to type up a similar explanation but you got there first. The write is the killer on the SSDs. Putting the OS and primary applications on it with swap/page on a hard drive will improve the life time (write).

You are right of course, but...

I only said that's how long it would function if being continuously read, and made no mention of writes.

Still, I don't think an SSD will be written that many times. Anyone that can afford an SSD for their boot drive is probably using at least 4GB of RAM, obviating the need for a swap file.

And if someone with 4GB of RAM does still in fact need a swap file, wouldn't their money be better spent on additional RAM?

But OK, let's pretend that we write to the drive alot, for whatever reason. That would only shorten the lifespan to closer to a human lifetime!

Not to mention this ignores firmware and driver improvements that effectively allow more write cycles.

I think it's still fair to say your SSD will outlast every single other component in your computer (at the worst), and outlive the operator (at best)!

I remember an article in PC World (UK version) that looked at the idea

of building a PC around a solid state card.

The conclusion was that it was not viable to put the OS on the card.

Now that was a few years back, things may have changed

Yep, things have totally changed. I won't put an OS on a hard drive again.

Once you go SSD, there is no going back...

I guess the life span is about the same as a HD, considering how many HDs I have lost over the years I can't imagine it to be worse, actually. In any case, a daily backup is a must for me so I am not even thinking about that.

One of the reasons I got the Intel HD is because of reputation - Intel isn't going to produce a SSD that dies within a few years. It's a bit like buying a Toyota - you trust in their ability to produce parts that are of a high quality.

If you want the SSD with the biggest capacity and lowest price, then go to Kingston.

You can check the price list on JIB.

Paying extra money for a high-end SSD is not a very good idea since the roundup review from tomshardware had proved that..

Would completely disagree, order of preference:

1. OWC 6G

2. Vertex 3

3. Crucial C300

"It's a bit like buying a Toyota - you trust in their ability to produce parts that are of a high quality."

Let me put it this way: I will ever use a hard disk as a main drive ever again. I will only use them for bulk storage (eg. my NAS box) and backup.

One unexpected benefit is that I can copy files off the network twice as fast as I could before. Previously, I was getting 50 MB/s pulling files from the NAS RAID (gigabit LAN), but its now 100 MB/s. Apparently, the bottleneck was not the LAN speed as I thought, but the hard disk in the PC.

In a couple of years I hope to be living in an entirely SSD world - hopefully by then SSDs will be cheap enough to use for bulk storage too. An SSD-based NAS box would be awesome.

1. OWC 6G

2. Vertex 3

3. Crucial C300

I've seen ADATA SSDs on Invadeit.com. Performance reviews show them as pretty good. Any experience or comments on this brand?

Never tried a Adata product no idea if they are Sata3 or what controller they use. (You want a sandforce chipset controller)

However I would stick with the above 3 brands plus Intel and Kingston. It's a lot of money to invest in a storage product so I personally would stick with the them as reviewed a lot on the net and lots of people using them on forums etc.

The vertex 3 takes some beating in Sata3 config and easily obtainable.