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Lost Capacity: Defining And Explaining The Scope

The OCZ Vertex 2 Conspiracy: Lost Space, Lost Speed?

There are two fundamental issues to explore here: lower capacity and reduced performance.

Capacity is easiest to address, so I’ll do that first. OCZ says that it is going 25 nm across its product line to bring costs down. But the entire lineup isn’t being affected capacity-wise. According to OCZ, only the 120 GB and 60 GB models are affected (note that our contact at OCZ in Europe says the 90 GB drives are affected as well, though OCZ's US office has not confirmed this)—it says it isn’t shifting to 25 nm on the 40 GB drives, and SSDs in excess of 120 GB don’t give up capacity because they already have enough leftover space to address the root cause of this whole brouhaha, which I’ll explain in more depth. Even more specifically, only the E-series drives are affected (OCZSSD2-2VTXE120G). It just so happens that I had a drive with the E firmware, and that’s what I also found on Newegg.

The E in that model name actually stands for Extended. At one time, all Vertex 2s employed 28% overprovisioning. E-versions facilitate less overprovisioning. Now, if you look at the following table, that seems like a counter-intuitive claim. According to OCZ, resellers haven’t been receptive to adopting new part numbers as these drives have changed. So, the E has really lost its original meaning.

IDEMA Capacity
Raw Flash Capacity
Windows Capacity
55 GB
64 GB
51.22 GiB
128 GB
107.10 GiB
64 GB
55.87 GiB
128 GB
111.75 GiB

I keep using the word “affected.” What does affected actually mean? With 64 Gb, 25 nm memory ICs onboard, more space has to be dedicated to SandForce’s Redundant Array of Independent Silicon Elements technology, which is tasked with improving reliability even in the face of block failures. That’s why you see lower capacities on the 120 and 60 GB models.

Why the bigger concession for RAISE? Currently, it’s being claimed that OCZ is setting aside more space for potentially bad blocks due to the 25 nm geometry. Twenty-five nanometer NAND has a harder time maintaining its structure than 34 nm NAND, so you get fewer write cycles out of it. SandForce skirts the issue by simply giving the controller more room to set aside blocks that eventually go bad. In reality, OCZ is actually forced to set aside more space as an artifact of the new 64 Gb ICs. Since full (now larger) bit planes are used for RAISE, shifting from 32 Gb to 64 Gb creates that discrepancy in capacity by inherently allocating more space per die to RAISE. According to OCZ, there is no functional difference in the uncorrectable bit error rate in moving to 25 nm. It simply is what it is.

OCZ's 34 nm-based 120 GB Vertex 2OCZ's 34 nm-based 120 GB Vertex 2

But add up the fact that OCZ’s E-series drives were intended to squeeze down overprovisioning and the increased spare space set aside for ECC on 25 nm-based SSDs and you have a recipe for lower capacities. This is easily illustrated with my OCZSSD2-2VTXE120G. The first drive I received, based on 34 nm NAND, gave me 111.8 GiB (120 GB) of usable space. The second drive (exact same model number on Newegg) dropped to 107.1 GiB (115 GB).

Now, if you paid $250 for 111.8 GiB, you were paying about $2.23/GiB. If you pay $230 for 107.1 GiB, you’re paying $2.14/GiB. During a recent chat with Ryan Petersen, OCZ’s CEO, he noted that the shift to 25 nm is intended to lower the prices on SSDs, since the devices themselves cost less. Based on today’s pricing, Ryan’s reasoning holds up—we are, in fact seeing more aggressive prices.

Also based on a 16-chip design, the 25 nm-based Vertex 2 is a completely different PCBAlso based on a 16-chip design, the 25 nm-based Vertex 2 is a completely different PCB

But what if you bought one of the new drives last month when they transitioned, but prices hadn’t yet adjusted? Even more importantly, what if you had a 34 nm 120 GB Vertex 2 and now want to add a second drive in RAID 0 without mismatching the capacities? Certain customers are right to be upset about a capacity change unaccompanied by a SKU adjustment.

For those folks, OCZ is offering to swap out 25 nm drives with 64 Gb NAND for drives with 32 Gb NAND, which reverses the capacity loss. At first, it was asking that customers pay the difference in NAND costs. I didn’t like that plan much because the potential was there to penalize customers who bought the new version legitimately hoping to match it up to an old drive in RAID, only to discover its divergent specs, or even the customers who read a review of the 34 nm NAND-based drive and expected the same ~112 GB to show up. Now, OCZ is stepping up to offer the swap at no charge, which we applaud.

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  • 3 Hide
    Anonymous , February 21, 2011 5:10 AM have a letter posted on the website that they will not be going to 25nm as the drives life cycle is less than half that of a 3*nm drive. Also the performance is not there.
  • 1 Hide
    cangelini , February 21, 2011 5:25 AM have a letter posted on the website that they will not be going to 25nm as the drives life cycle is less than half that of a 3*nm drive. Also the performance is not there.

    Depending on supply of 34 nm NAND, that's probably not a sustainable position to take. IMFT isn't going to decide to shift back to 34 nm.

    At the risk of contradicting myself, Intel will be using 34 nm NAND on its next-gen 6 Gb/s Elmcrest drives. It's not like the flash isn't disappearing entirely, but the vendors making the switch seem to be motivated largely by cost-cutting reasons.
  • 4 Hide
    radiovan , February 21, 2011 6:04 AM
    Nicely done Mr. Angelini; however, I still think OCZ pulled a nasty car-salesman tactic on their newest 25 nm NAND SSD products, and as such will be looking elsewhere to purchase any future SSD. Blaming resellers or other sources for the SKU is an incompetent way of deflecting fault and has made them look even more silly.
  • 1 Hide
    cangelini , February 21, 2011 6:17 AM
    Thanks radiovan. Like I mentioned in the story, we'll have to see if companies like Corsair and Patriot are able to get their upcoming renamed SKUs onto Newegg, Tigerdirect, Zipzoom, etc.
  • -1 Hide
    binoyski , February 21, 2011 6:40 AM
    Ok, but when will we be able to buy ssd's that are $100 @ 1TB capacity?
  • -1 Hide
    Anonymous , February 21, 2011 7:28 AM
    1.29 nice... pity that ocz only documents 1.28 for the moment.

    And then again why not update the 25nm to 1.29 too?

    But I guess consistency is not always wished when trying to demonstrate something
  • 1 Hide
    nebun , February 21, 2011 8:24 AM
    binoyskiOk, but when will we be able to buy ssd's that are $100 @ 1TB capacity?

    in about 10 years or so....that's a very big maybe
  • -1 Hide
    dconnors , February 21, 2011 8:29 AM
    Don't lie, Chris. We all know you still have (and love) that little Miata.
  • -1 Hide
    yose3 , February 21, 2011 8:29 AM
    binoyskiOk, but when will we be able to buy ssd's that are $100 @ 1TB capacity?

    when you throw a shoes to bush again meaby lol
  • 2 Hide
    Reynod , February 21, 2011 8:45 AM
    It is all about profit.

    The real reason is that going to cheaper flash with a 3000 cycle life to reduce the total cost of production (and therefore increase profit) means ... increasing the amount of redundant memory to replace the flash that dies due to wear ... and that process means better error correction is required to achieve that ... therefore performance is effected.

    Chris ... I got it into one sentence ... albeit a horrible one.

    Nice article mate.
  • 0 Hide
    cangelini , February 21, 2011 8:57 AM
    meanon1.29 nice... pity that ocz only documents 1.28 for the moment.And then again why not update the 25nm to 1.29 too?But I guess consistency is not always wished when trying to demonstrate something

    Update your drive with the 1.28 toolbox--it'll show up as 1.29 :) 
  • 0 Hide
    hannibal , February 21, 2011 10:06 AM
    Well normally moving to smaller production technology has mean better performance. I am not sure if the new situation where newer technolygy is inferior compared to old took manufactures by surprice?
    But in anyway their own tests should have shown it...

  • 2 Hide
    mike2100 , February 21, 2011 11:35 AM
    Mazda did the same thing in 2004 with the RX-8. Originally advertised 255hp dropped to 238 and it offered to buy back cars.

    Very bad move on OCZ's part. Justified or not, many people who hear this news will not be buying an OCZ drive.
  • 2 Hide
    JohnnyLucky , February 21, 2011 11:43 AM
    Great article.

    It appears as if OCZ was the first to market which would normally mean press releases, announcements, lots of hoopla, and technical reviews. Instead, OCZ chose to remain silent until customers complained. Silence had to be a management decision. What did management know?
  • 1 Hide
    JohnnyLucky , February 21, 2011 11:51 AM
    BTW - Veteran posters at Tom's Hardware might remember what happened when OCZ acquired PC Power and Cooling. PCP&C had some of the best high quality power supplies available until OCZ acquired the company.
  • -1 Hide
    saint19 , February 21, 2011 11:51 AM
    The same was for Toyota with his brakes problems few years ago.

    OCZ is a good manufacturer, but at this point when they are out of the RAM business, they need fix that problems and avoid futures ones if OCZ as company wants be on the market for more years in future.
  • 2 Hide
    rantoc , February 21, 2011 12:20 PM
    So they pushed out a cheaper less performing model with same name and stayed quiet about it, not the best way to get customers to return to the brand!

    I don't like the idea of 25nm flash for several reasons, reliability is my main concern. Sure there are better block handeling in the last gen sandforce controllers (vertex3) but what about quicker dying cells and when the controller runs out of spare cells! When it comes to storage i rather let the tech mature at the expense of early adopters (paying betatesters!?) than have to restore an old backup and hassle with RMA.
  • 1 Hide
    Anonymous , February 21, 2011 12:34 PM
    The "mistake" by OCZ was not a mistake at all.
    They are doing the same thing as before...
    With their Rally 2 USB drives to be specific.
    The Rally 2 did not have a model change at all (although it did have a different LED color), but users suddenly found out the new Rally 2 drives did not work in Xbox 360s and were slower.

    OCZ has been great with their SSD customer support, but this fiasco was a huge slap in the face to all of their fans.
    I know my next SSD will most likely be another brand unless the price is considerably less.
    It will most likely be a Corsair, Crucial, or Intel. Corsair, because they were completely up front with their transition to 25nm and will also continue to have the Sandforce based chips for their future SSDs.
  • 1 Hide
    compton , February 21, 2011 12:57 PM
    Good job, Chris.

    I'm glad the crew at Toms is on the case. A thorough analysis indeed. Keep it up.

    As a side note, I think I may stick with the 34u NAND drives for my third SSD purchase. I would always like more performance, but an SSD is basically destroying itself slowly. The biggest chunk of performance is gained simply by transitioning from HDD to SSD for OS and applications. Everyone wants a faster drive, but I also want my drives to last for a while. I'm concerned that reliability of ALL devices may suffer with smaller lithography. Maybe is't unwarranted concern. Time will tell.
  • 0 Hide
    scook9 , February 21, 2011 1:30 PM
    I got the 120GB Vertex 2 on the Jan 31 Shell Shocker on Newegg, since then I have been UNHAPPY with its performance. Now I know why.....I also had noticed the performance was lower than it should be

    I got the drive and threw it in the desktop to test before putting it in the laptop. Everything looked good. Threw it in the laptop and installed Windows 7 and a few basic programs. Performance now SUCKED (read was like 5% slow - 25% in 4k, and writes were all about %50 of what they should have been). Angry, I thought, maybe the laptop is bottlenecking it, threw the drive back in the desktop. Lo and behold, same abysmal performance. This was all with the drive having an on-time of about 45 hours since manufacturing......virtually NO use. I have now secure-erased the drive and that seems to have temporarily restored performance although the 4k speeds are still about 10 MB/s low (high 20's instead of high 30's)

    I have 6 SSDs right now and this is the only one I do not like. I am actually the happiest with the A-Data S599 rebrands that MicroCenter is selling (the $110 64GB ones - got 3).

    SO, I am interested in this thing that OCZ is doing, is that simply changing the chip density or also getting you a drive with 34nm chips on it? Will either do that or have newegg swap the drive with a different brand for me
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