OCZ Vertex 4 256 GB Solid State Hard Drive SSD Review

The Vertex 4 is a departure from OCZ's tried and true model of using third party controllers and firmware for its SSDs. Taking control of the firmware with the Vertex 4 gives OCZ the ability to tune the SSDs for speed and performance at lower queue depths and optimize for low latency. We test to see if the Everest 2 Platform delivers.



The Vertex 4 has certainly had its fair share of attention with the radically different performance characteristics that have left many scratching their heads.

The initial specifications look very impressive at first glance, with up to 550 MB/s in sequential read speed. 120,000/85,000 possible read/write IOPS also goes a long way towards impressing the crowd, with the 120K read IOPS leading the consumer SSD market. An eight-channel dual-core ARM processor (Marvell 9145) does the heavy lifting while the Indilinx Infused Everest 2 Platform is the brains behind the operation. A major departure for the Vertex series, which used to sport the LSI SandForce range of controllers, is that the controller and firmware do not rely upon compression for the Vertex 4's performance.

Part of the Indilinx firmware is the new Ndurance 2.0 technology. This sophisticated method of NAND management purportedly increases the reliability and durability of the NAND employed. Utilizing advanced signal processing and a multi-level ECC engine the firmware is dedicated to data protection. The Vertex 4 also takes significant steps towards mitigating the effects of write amplification by improving the efficiency of the read-write-modify process that is required for each write to the NAND. Write combining, to minimize unnecessary writes to NAND, is probably furthered by the large amount of DRAM that is built into the SSD. The 512MB of DRAM cache on-board the 256GB SSD provides plenty of buffer for the drive, and the 512GB version packs a whopping 1GB of DRAM.

One of the more interesting inclusions is voltage shifting, which alters the amount of voltage used to program the NAND. Utilizing lower voltages to program NAND cells results in much higher endurance from MLC NAND.

In the event of data corruption Ndurance 2.0 also has the optional Redundant NAND Array technology, which provides parity data striped across the NAND packages. Unfortunately this isn't utilized in the Vertex 4, though it will come at a loss to some capacity, most likely with enterprise iterations of the SSD.

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So what are the unexpected caveats with this SSD?

Simply put, it is geared towards low queue depth random read and write performance. The low queue depth sequential reads suffer, coming in much lower than other SSDs in the market. With the initial firmware version (1.3) the low QD sequential read performance was much slower than competitors. The newer 1.4 and 1.5 firmware (we are testing 1.5) has made notable improvements in this respect but they remain markedly lower than competitors do.

Perhaps the most controversial aspect of the drive is the distinction between a 'Performance' and 'Storage' mode for the Vertex 4. This is an anomaly that many reviewers did not come upon during the initial round of reviews and tests with the newer firmware revisions.

When the SSD is below 50% capacity the drive will have a much higher sequential write performance. Once filled above this mark however the SSD suffers a very large loss of sequential write speed. Many were quick to decry that OCZ was playing games with their firmware to hide the slow sequential write speed issue. Precious few reviewers will test with any data on the drive or in steady state conditions, which concealed the issue in many evaluations.

OCZ released an official statement stating that at lower fill percentages the Vertex 4 will operate in a Performance mode, and once full the SSD will switch to the Storage mode, which has much lower sequential write speed. This is a one-time change that we can actually monitor and see in HDTune results. Since we feel that the Storage mode is indicative of the real performance of the Vertex 4 for the majority of users our HDTune testing will reflect these values.


The Vertex 4 comes in four capacities. The differing capacities do have slightly different specifications, which are listed below.

The 64GB retails for $72.98, the 128GB retails for $109.99, the 256GB for 199.98, and finally the big kahuna 512GB is going for $388.99, which is really a steal for that capacity. (Prices on SSDs fluctuate constantly so we advise make sure to check the prices overall before buying.) Overall the pricing range for the Vertex 4 remains competitive with others in the market, even though the prices do fluctuate drastically. We will have a complete breakdown of the prices compared to competing solutions in the conclusion.


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  • Physical

  • Usable Capacities (IDEMA) -- 64GB, 128GB, 256GB, 512GB

  • NAND Components -- 2Xnm Synchronous Multi-Level Cell (MLC)

  • Interface-- SATA III / 6Gbps (backwards compatible with SATA II / 3Gbps)

  • Form Factor -- 2.5 Inch

  • NAND Controller -- Indilinx Everest 2

  • DRAM Cache -- Up to 1GB

  • Dimensions (L x W x H) -- 99.8 x 69.63 x 9.3 mm

  • Reliability/Protection

  • MTBF-- 2 million hours

  • Data Path Protection-- ECC corrects up to 128 random bits/1KB

  • Data Encryption-- 256-bit AES-compliant, ATA Security Mode Features

  • Product Health-- Self-Monitoring, Analysis and Reporting Technology (SMART) Support

  • Environmental

  • Power Consumption-- Idle: 1.3 W Active: 2.5 W

  • Operating Temperature-- 0آ°C ~ 70آ°C

  • Ambient Temperature-- 0آ°C ~ 55آ°C

  • Storage Temperature-- -45آ°C ~ 85آ°C

  • Shock Resistance-- 1500G

  • Compatibility

  • Serial ATA (SATA) Fully compliant with Serial ATA International Organization: Serial ATA Revision 3.0.

  • Fully compliant with ATA/ATAPI-8 Standard Native Command Queuing (NCQ)

  • Operating System Windows XP 32-bit /64-bit; Windows Vista 32-bit / 64-bit; Windows 7 32-bit / 64-bit; Linux; Mac OS X

  • Additional Features

  • Performance Optimization TRIM (requires OS support), dynamic and static wear-leveling, background garbage collection, Indilinx nDurance 2.0 Technology to extend SSD lifespan

  • Other Performance Features Ndurance 2.0 Technology (Reduced Write Amplification without Compression, Advanced Multi-Level ECC, Adaptive NAND Flash Management)

  • Service & Support 5-Year Warranty, Toll-Free Tech Support, 24 Hour Forum Support