What is write limit for SSDs?

[miha2]

Hello. Choosing between SSD and hard drive (maybe 10K?): what is better and why. I'll be writing (and reading) lots of stuff on the drive. I've read that SSDs have a write (and read?) limits, is it really like this? Why would I even bother getting one? Also, I've read that there are MLC and SLC technologies. Is write limit on both technologies, or only one? Basically, I'm asking a question: What is best to get: big SSD, small SSD+HDD, or just HDD?

 

[sminlal]

Even though MLC-based flash memory has less write endurance than SLC, all consumer drives use the former because it's a lot cheaper. SSDs use controllers that include very sophisticated "wear-leveling" algorithms to make sure that no one flash memory cell will wear out first, and so the actual lifetime of an SSD is a lot longer than it would be otherwise.

As an example of endurance, Intel rates its 160GB X-25M G2 drives with a lifetime of "at least" 5 years even if you write 20GByte per day to them. I've used one in my Windows 7 system for well over a year now and it's averaged about 5GBytes worth of writes per day - so on that basis I'd expect it to last around 20 years. That's a LOT longer than I've ever used any other hard drive. In fact the only storage media I've used for that long are some old CDs I bought back in the 80's.

What most people who use SSDs do is to buy one large enough to hold the OS and applications, and also buy a hard drive to hold the rest of your documents, photos, videos, etc. That's a good compromise which puts the most performance-critical files on the fastest drive and has the cheapest cost-per-byte for your data files which typically have much lower performance requirements.

The only reason I can see to use just an SSD would be if you have a laptop that only has room for one internal drive.

 

[adampower]

The only reason I can see to use just an SSD would be if you have a laptop that only has room for one internal drive.

Or if you have storage elsewhere you may want a silent and fast pc with just an OS, office, couple of much used programs and use a NAS for photos and files, etc.

 

[miha2]

So, basically, if I use SSD to write data of, say, 1GB, I will be able to use it for 100 years, do you mean it like that?
And by the way, what is the best (longest for write (/read) limits) SSD? And, finally, how I should move my Page file and temporary folders to the hard drive?

 

[sminlal]

Or if you have storage elsewhere you may want a silent and fast pc with just an OS, office, couple of much used programs and use a NAS for photos and files, etc.

The biggest source of noise in most PCs is the fans. My desktop PC has an SSD, a 500GB WD Black drive and a 1TB WD Green drive - it's extremely quiet because it uses a passively cooled video card and very large-diameter slow-moving fans. Despite this, I still can't hear the hard drives. In fact I use bare WD green drives in an external USB drive dock to do backups, and even though they're sitting right out in the open about 2 feet from my ears I can't hear them either, except a bit when they spin up as the power is turned on.

 

[adampower]

That's write. haha. Each nand cell can survive a certain amount of writes before it deteriorates.

The 'old' intel G2 drives and any drive with 34nm NAND will last longer. New OCZ vertex 2 drives and next gen drives are going to 25nm nand which takes a hit.

In mho moving page file and temp folders is unnecessary but there are a couple of good SSD TWEAKs you can search easy enough via google or in these forums.

edit

he beat me by that much...

Also, moving the page file and temp folders arguably slows down the OS slightly which is the whole reason for having an SSD anyway.

 

[sminlal]

So, basically, if I use SSD to write data of, say, 1GB, I will be able to use it for 100 years, do you mean it like that?
And by the way, what is the best (longest for write (/read) limits) SSD? And, finally, how I should move my Page file and temporary folders to the hard drive?

Yeah, 100 years at 1GB/day would be equivalent. Although you have to understand that flash memory technology relies on static charges to retain data - those charges will eventually dissipate. What I've seen suggests that you shouldn't depend on data being retained for longer than about 10 years - so as long as you reformat your drive and reinstall everything every 10 years you should be good for a century. Of course in 20 years your biggest problem will probably be finding a computer with a SATA connection to plug your drive in, since "technology always marches on".

Unfortunately write endurance figures seem to be hard to come by. One of the reasons I chose Intel was because they published their figures and they gave information about how their controller achieved them.

I personally disabled my pagefile altogether because I have 12GB of RAM and never get close to using it all - so a pagefile is superfluous for me. I left the temporary files on the SSD so that software which uses them (such as Internet browsers) get the best possible performance from them.

 

[miha2]

OK. So, basically, out of the info provided, I can assume that I can use Intel's 40GB SSD (about $100) for as long as 25 years if I download (=write and then read later) a 4GB file every day. I hope it to last THAT long, since I don't want to back it up for later, assuming that I might need to just reinstall an OS (I don't think it's possible to back it up, right?) in 20 years, since as you said, it'll be hard to find a good motherboard with SATA port in the future. I hope my computer to live for that 20 years, and then just to build a new one. And by the way, which SSD were you talking about, Intel's for 5 years? I found only for 3 years (40GB)

 

[adampower]

size matters... a 160gb drive has 4 times the nand of a 40gb (almost). Therefore your 4gb files will spread over more nand.

I don't know what to say. 20 years ago I was probably using a 386 16mhz with 4mb ram and a 40mb hard drive?

$100 spread over 5 years is $20/year or less than $2/month. A 5 year life span is more than enough for me.

 

[sminlal]

The 20GB/day for 5 years applies to the 160GB Intel X25M G2 drive. Although I haven't seen a figure for the smaller drives, I have to assume that it would be less, because as adampower says there are fewer cells to spread the writes over.

 

[miha2]

For me, the longer the drive lives, the better. And by that, I mean that if I can write lots and lots of data for at least some short period (5-10 years, or more) of its lifetime (on today's SSDs it's about 1,000,000 hours long, or more than 100 years), then I can call it an SSD. Not like write and erase, write and it dies. So, basically, I mean that the computer is supposed to live for about 10 years, after which the processor, motherboard, hard drive, power supply and other parts wear out, and it's easier to build a new PC, than repairing old, since it'll be hard to find the parts for it. That is why I need an SSD for 10 years, not less. By the way, I built my computer 1.5 years ago, so assume I'll be writing data every day, about 1GB - 9GB, for 8.5 (or possibly more) years. So, I assume that provided here 160GB Intel X25M G2 drive is the best for my situation, even though it's pretty expensive. By the way, on NewEgg.com I found 3 SSDs of the X25M G2, and all 3 are for 3 years warranty. Finally, are PCI-e SSDs any better than SATA's? I don't mean speed, I mean all the same write limits.

 

[adampower]

Same NAND in PCI-e. I think there are only two manufacturers of NAND? (really out on a limb here). But, regardless the 34nm process is what it is.

Also, you can put downloads on your spinning disks. There's not much benefit to writing to the ssd especially from d/l. In fact most spinners can write sequentially much faster than the intel ssd. It's the access time that makes the solid state drive awesome. But, which spinner will last 10 years you ask...

All in all I respect what you're doing and wanting to do. AND you can likely be using your computer happily in 8-10 years. I find my time between builds is growing longer as well.

Good luck.

 

[miha2]

OK. I see it, thank you all for your answers. I really appreciate them.

 

[miha2]

Best answer selected by miha2.

 

[hwnmafia02]

man are you serious just do what we all do

get the SSD, replace it when it dies.

store your stuff on a RAID5 array and expand it as needed.

and run the games from the SSD. lots of reads, very few writes (unless recording a demo).

 

[Mousemonkey]

This topic has been closed by Mousemonkey