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hekokimushi
Dec 12, 2011, 02:31 AM
Hi,

searched all over, without much luck.
Samsung and Toshiba are the well known OEM providers for MBA's SSD.

aftermarket one's are OWC that we all know about.
i have come across a set that claims to be fully compaitble with the MBA latest model, both physically and pin outs. but lack of information regarding its data put through rate and datasheets. please see attached for info. Brand is well known: SanDisk. controller seems to be independent, not SandForce. Trim? no idea. all i know, it is 128Gb.

please fill me in if you have any knowledgeable info. best regards
h:apple:



oneMadRssn
Dec 12, 2011, 04:45 PM
Out of curiosity, where did you find this?

Honestly, with the reliability of SSDs being questionable, I would not put in something that wasn't very well covered by warrantee from a reputable source. Specifically: I trust Apple will not give me any grief about the stock SSD if something goes bad, and I trust OWC as I hear their support is also top-notch.

But the MTBF for SSDs is still fairly low, not worth the risk to save a few bucks and buy from a questionable source.

Smileyboy
Dec 13, 2011, 07:27 AM
What does that ssd cost?

MrWillie
Dec 13, 2011, 08:52 AM
.
But the MTBF for SSDs is still fairly low, not worth the risk to save a few bucks and buy from a questionable source.

Link please. MTBF of modern SSDs is extremely high. Way past that of conventional drives.

http://www.intel.com/design/flash/nand/extreme/index.htm

Intel SSD with a 2 million hour MTBF. Others are rated between 1 and 2 million hours.

oneMadRssn
Dec 13, 2011, 09:57 AM
Link please. MTBF of modern SSDs is extremely high. Way past that of conventional drives.

http://www.intel.com/design/flash/nand/extreme/index.htm

Intel SSD with a 2 million hour MTBF. Others are rated between 1 and 2 million hours.


You're correct. Intel-made server-grade SSDs are extremely reliable, far more so than spinning platters. No doubt about that.

But anecdotally, I know that sandforce controlled SSDs tend to fail as higher than ideal rates. That includes a lot of consumer-grade, who-the-hell-knows-made, SSDs. Other controllers, such as Intels, tend to do better in consumer-grade stuff, but there are still lots of horror stories online of endless returns.

Regarding your article, the 2-million hour MTBF has been criticized and scrutinized all over the place. First of all, its impossible to verify without sitting with a drive for nearly 300 years. Second of all, that figure doesn't account for the multitude of reasons an SSD can fail, such as manufacturing defect. They assume you start with a perfect drive.

vitzr
Dec 13, 2011, 11:57 AM
MTBF for SSD's is just a number at this relatively early stage in their implementation, where Apple computers are concerned.

I've actively been using & evaluating many different SSD's over the last few years and find thus far, Windows 7 handles them much better than OS X Snow Leopard. Lion's far too new to evaluate just yet. We do know it's better, but many questions remain.

The point is not that Windows is better, but rather the fact that it's the OS that impacts how well an SSD operates in any given computer. Therefore MTBF is nearly meaningless.

Apple being the highly secretive, proprietary company it is, most probably installs highly optimized SSD's in their new laptops that are nearly impossible to match with 3rd party SSD's available to consumers at this juncture.

So far when it comes to Apple I've had very good luck with both Intel & Samsung SSD's (in the 15" MBP's used for testing) yet I have less than one year on them, therefore it's too early to determine just what the long term success will be like.

That said, my suggestion to those who are considering the purchase of an MBA, is to very carefully consider your storage needs before choosing which model you buy. Then buy appropriately. The OEM SSD Apple includes is far better than an aftermarket substitution at this point.

MrWillie
Dec 13, 2011, 06:18 PM
You're correct. Intel-made server-grade SSDs are extremely reliable, far more so than spinning platters. No doubt about that.

But anecdotally, I know that sandforce controlled SSDs tend to fail as higher than ideal rates. That includes a lot of consumer-grade, who-the-hell-knows-made, SSDs. Other controllers, such as Intels, tend to do better in consumer-grade stuff, but there are still lots of horror stories online of endless returns.

Regarding your article, the 2-million hour MTBF has been criticized and scrutinized all over the place. First of all, its impossible to verify without sitting with a drive for nearly 300 years. Second of all, that figure doesn't account for the multitude of reasons an SSD can fail, such as manufacturing defect. They assume you start with a perfect drive.

If you write to several bits over and over, you can then analyze the data degradation. Then if you take into consideration the speed of the controller/buss, the size of the drive (larger is better), and the numbers of reliable writes per bit, you come up with a life expectancy of like a little over 50 years for a 64 Gig drive. Larger drives have longer lives because the writes are spread across more bits. I did the math for someone once.

Of course this doesn't take into consideration controller failures. I would trust a SSD over a conventional any day, especially in a laptop.