OCZ's Vertex 3: Second-Generation SandForce For The Masses

Inside OCZ's Vertex 3

This is a performance preview based on a pre-production piece of hardware. We should see drives pop up in retail sometime in mid-March. Until then, all beta samples, including the one in our SoCal lab, employ Micron’s 25 nm 8 GB (64 Gb, 2-bits per cell) ONFi 2 (synchronous) MLC NAND in an eight-channel configuration. Final production units will use NAND from Intel, but since both come from IMFT, there shouldn’t be any difference between them. With that said, the firmware isn't final and OCZ is still experimenting with performance, hence the sequential write speed increase seen after last week's Vertex 3 Pro coverage.

When it comes to capacity, our 240 GB drive turns out to be 224 GiB in Windows. For those curious, let’s run through the math. We have 16 NAND devices. Each device has two 8 GB MLC dies, which comes out to a total of 256 GB. This means that 16 GB is reserved for data parity (8 GB for RAISE), garbage collection, block replacement.

IDEMA Capacity
Raw Flash Capacity
Capacity in Windows
Vertex 3 100 GB
100 GB
128 GB
93.3 GiB
Vertex 3 240 GB
240 GB
256 GB
224 GiB

As of today, OCZ is planning to launch two different capacities of the Vertex 3: 120 GB ($249.99) and 240 GB ($499.99). Those prices are significantly lower than what you would pay for a Vertex 3 Pro. So what is different? Two things.

  1. Consumer-grade controller. We'll explain this below.
  2. Power protection. Unlike enterprise drives like the Vertex 3 Pro, you don't see a supercapacitor (a component that allows the drive to make sure buffered data is written to the flash). This isn't something to fret over, though. If you plan on throwing a SSD into a laptop, a power failure isn’t as important to you as it is to the enterprise client in a mission-critical application.

SandForce: Consumer Flavors

The most interesting part of this preview has to do with the SF-2281 controller at the heart of our Vertex 3 sample. How does this differ from the SF-2581 on the Vertex 3 Pro? Bear with us; the answer gets a little involved because SandForce is actually announcing a total of four controllers today. We're going to see them all used at some point, so let's break them down from the outset.

- SF-1222 SF-2141 SF-2181 SF-2281 SF-2282 SF-1565 SF-2582 SF-2682
Target MarketClientClientClientClientClientEnterpriseEnterpriseEnterprise
SATA Interface3Gb/s3Gb/s3Gb/s6Gb/s6Gb/s3Gb/s6Gb/s6Gb/s
MB/s* (Seq Read/Write)250/250250/250250/250500/500500/500250/250500/500500/500
IOPS* (Sustained 4 KB Reads)30K60K60K60K60K30K60K60K
IOPS* (Burst/Sust 4 KB Writes)10K60K/10K60K/20K60K/20K60K/20K30K60K/60K60K/60K
SMART AttributesBasicBasicBasicBasicBasicExtendedExtendedExtended
Package TypeBGA-361BGA-256BGA-256BGA-256BGA-400BGA-361BGA-400BGA-400
Max Capacity GB51264256/512256/512512512512512
ECC (max bits/512B sector)24 (RS)55 (BCH)55 (BCH)55 (BCH)55 (BCH)24 (RS)55 (BCH)55 (BCH)
AES Encryption (bits)128256 & 128256 & 128256 & 128256 & 128128256 & 128256 & 128
Military EraseNoNoNoNoNoYesYesYes
iTemp OptionYesNoNoNoNoYesYesYes
non-512 Byte SectorsNoNoNoNoNoNoNoYes
Power Fail Circuit SupportNoNoNoNoNoYesYesYes
Minimum Over Provisioning7%0%0%0%0%28%28%28%

The SF-2141/2181 is slated to effectively replace the older SF-1222, even though the older controller will persist for at least another year. The entire SF-2100 series realizes enhanced random read/write performance, but only the SF-2181 supports capacities higher than 64 GB. Both controllers are still SATA 3Gb/s parts, but they support newer versions of the toggle-mode and ONFi 2 interfaces. As manufacturers stop making older flash, SSD makers will have to move to new flash interfaces. Thus, companies like OCZ will have to use a controller compatible with those technologies.

The SF-2281 is physically the same chip as the SF-2141 and SF-2181, but it employs SATA 6Gb/s. This isn't necessarily part of the hardware design. The short answer, though, is that you cannot buy a SF-21xx based drive and hope to "unlock" 6 Gb/s connectivity.

Meanwhile, the SF-2282 is physically the same as the SF-2582 (seen on OCZ’s Vertex 3 Pro) and the SF-2682 (SAS). All three SATA 6Gb/s controllers support sequential read and write speeds of up to 500 MB/s and random 4 KB writes up to 60 000 IOPs. The difference is that the SF-2282 has capped random write throughput of 20 000 IOPS. This is purely a firmware limitation, as SandForce believes that 20K is high enough for PCs in a client environment.

Having gone through the difference, we quickly realized that OCZ is claiming performance in excess of what SandForce cites for the SF-2281 controller. The drive is supposed to see a sequential read up to 550 MB/s and writes up to 525 MB/s. So, what gives? Well, OCZ is employing its home-brewed firmware. The company isn't able to give us a solid number on what to expect for sustained random write performance, but we are told the drive should running beyond the sustained 20 000 IOPs spec. This gives you an idea of what we should see in benchmarks.

Beyond performance, the three remaining major differences between an enterprise and consumer controller are power protection, reliability, and diagnostics.

  1. Power protection. The SF-2500/2600-based drives employ a supercapacitor, and as we already covered, this is more of an issue if you are deploying drives in a mission-critical environment.
  2. Reliability. We’ll cover more this separately, as it is rather involved.
  3. Diagnostics. Enterprise consumers need to the ability to debug, log, and diagnose any potential failure, which is why the SF-2582 and SF-2682 have an enhanced set of SMART attributes.
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  • Ten98
    That $1000 build sucks out loud. SLI is a worthless technology and those graphics cards are old. You could easily swap the crappy SLI setup for a single GTX 560Ti, step down to a 500W PSU and add a Vertex 2E for ultimate Windows performance and super fast game load times.
  • peter2112
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  • may1
    Ten98That $1000 build sucks out loud. SLI is a worthless technology and those graphics cards are old. You could easily swap the crappy SLI setup for a single GTX 560Ti, step down to a 500W PSU and add a Vertex 2E for ultimate Windows performance and super fast game load times.

    Why would you even talk about GPUs? This is supposed to be a test for SSDs.