OCZ Z-Drive R4 C PCI Express 1.6TB SSD Review – OCZ Z-Drive R4 versus FUSION-IO ioDrive Duo

The OCZ Z-Drive R4 PCI Express SSD contains eight SandForce SF-2281 processors, 128 pieces of NAND flash memory and a Superscale Storage Controller. If ever a MONSTER storage device was created, the R4 definitely answers that call.

In fact, a simple review just doesn’t seem appropriate for the OCZ Z-Drive R4 (Z-R4).  Let’s throw it in the ring against FUSION-IO’s ioDrive Duo (io-D), see who can go all twelve rounds and emerge the true heavyweight champion.  Let the storage wars begin!


OCZs track record over the past few years shows them to be no less than a leader in SSD innovation and much of what they have accomplished has yet to be matched by their competition.  The RevoDrive line of PCI Express SSDs is a perfect example as it still has no competition for its performance and price. Currently, OCZ seems to have revamped the industries idea of what a hybrid drive should be and  will soon be releasing the RevoDrive Hybrid, capable of 910MB/s read and 810MB/s write performance.  If that weren’t enough, they  have  they have also just announced the new Synapse Cache 6Gbps SSD line which will again revolutionize the way we interact with hard drives.

OCZ continues to answer consumer demand for higher performance, yet again, by hooking the PC enthusiast (or ‘prosumer’) with the Revo 3 line and it appears that they are now setting their sites on the enterprise market with the new Z-Drive PCI Express solid state drive.

One could easily argue that they have already done that with with their RevoDrive 3×2 series that we recently reviewed, however, it seems that speeds of 1.5GB/s read,  1.25GB/s write and 200,000 IOPS at 4k aligned random disk access simply aren’t enough. The introduction of the Z-R4 sees OCZ doubling performance once again and almost appearing to ready to move in on the PCI Express SSD marketshare presently controlled by FUSION-IO.


You won’t find a publicly available price for the Z-R4 anywhere and I can add that many hours of trying to manipulate OCZ executives has met with little success as well.  The Z-R4 is an enterprise product and will be built to specifications as detailed by each customer.  OCZ will, however, be building a standard preconfigured set of Z-Drives available for immediate purchase through their enterprise distributors. We are told that direct customers can immediately meet with the OCZ Enterprise Sales Team as the Z-R4 is sampling today.

What we can say is that the Z-R4 sells for approximately $7/GB, a price less than half of that of the io-D which stands at over over $15/GB.  This can become a ‘no brainer’ for enterprise clients when they consider the ‘cost per IOP’ in comparing the Z-R4 to any PCIe or traditional rotational base storage array solution.  Now, throw in the fact that the Z-Drive is a bootable solution whereas the io-D is not and the Z-Drive takes ‘Round One’ hands down.


blankThe Z-R4 is capable of 2.8GB/s read and write performance with 440,000 IOPS at 4k random aligned write disk access.

That’s just the beginning as OCZ can easily configure the Z-R4 with two of their Superscale Storage Controllers and double performance to 5.6GB/s read and write with 1.2 million IOPS at 4k random write aligned disk access.  Is there really a need for anything that fast?

The FUSION-IO ioDrive Duo specifications describe 1.5GB/s read and write performance with 4k random aligned write disk access of 250,000 IOPS.


The Z-R4 comes with a three year warranty and is available in several configurations to include C or R Series, half or full height form factor, eMLC, MLC or SLC NAND flash memory, as well as single or dual Superscale Storage Controllers.  Its sizes start at 300GB (depending on configuration) and stretch as high as 3.2TB.  Initial specifications describe the R Series as having Power Fail Protection and DataWrite Assurance Technology whereas the C Series does not. Our test sample is the C Series.


blankThe Z-R4, as well as the new Revo lines, is based on SCSI (Small Computer Systems Interface) technology and is not a ‘RAID’ configuration as many seem to be stating.  Both the Z-R4 and Revo lines support TRIM, however the present Microsoft Windows Storport architecture does not support SCSI UNMAP or TRIM.  As a result, TRIM does not function in any of these drives as the commands are not generated by the OS for the Z-R4 execute.

From a personal viewpoint, TRIM has become secondary in nature and probably unnecessary, in any case, due to the excellent ‘garbage collection’ abilities we are seeing in SandForce hardware.  The initial Revo and Revo x2 lines are a perfect example, all of which still maintain excellent performance through heavy use despite their lack of TRIM.

VCA 2.0

VCA 2.0 (Virtual Controller Architecture) is OCZs ‘Crown Jewel’ so to speak and you won’t see it made available to other manufacturers any time soon.  Both the Z-R4 and Revo 3 lines contain VCA 2.0 and, similar to SandForce’s secret to SSD storage compression, this is a concept not easily explained to the average reader.  We provided a brief explanation in our RevoDrive 3×2 Review and OCZ offers a VCA FAQ Page to assist as well.


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    Would be more fair if you compared it to the 1.28 TiB variant of the Duo.
    Brilliant article none the less…

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      I agree totally but we have to work with the hardware that we have access to. As for the compliment of it being a brilliant article, totally unexpected and thank you very much.

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        “we have to work with the hardware that we have access to”

        OK, so you have access to the fastest OCZ hardware but not the fastest FIO hardware…and this makes for a subjective test? Seriously? When do you expect to have current hardware for live testing? Any chance we might get actual server-side testing to show off the true strength of FIO hardware and, more importantly, software? Oh wait, then we couldn’t have a test could we…you’d need a competitor other than OCZ….

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        WE would be pleased to hear suggestions as to other sources of competition for the card. Thanks ahead.

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        not sure why the harsh response or love affair with Fusion. Why do you care which company? I say Fusion should put up the hardware like OCZ and do real life tests within applications. Both companies can put there money where their mouth is.

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        Harsh response? Love affair? I guess I am a bit confused because, well, myself, when I read an article I want to know the reviewers opinion and feelings just as much as I do facts alone. This is what keeps my interest.

        It is also an important factor to help the reader. Take for instance the stuttering 602 controller a few years back. Can you imagine a reviewer saying, ” The drive stalls and stutters a bit but is still a large step up from a hard drive” Say it like it is I believe and hope our fellow members feel the same.

        Thank you for taking the time to respond and expressing your feelings.

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        This is subjective because the z-drive r4 is cheaper than the FIO drive.

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        You find it subjective because one performs alot better yet is alot cheaper? How so?

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    Please update using the ioDrive 2 they just released, also

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    Finally SSDs start approaching the RAM speeds. Not very useful yet for the regular users without deep pockets. So meantime we still get 2-5 times of these speeds with software based QSoft RAMDrive and, thanks to DRAM price drop, at the $5/GB. While many even never heard of that but we are enjoying such crazy RAMDrives’ speeds for our apps for almost a quarter of century since the DOS times.

    Suggestion to authors – test it just for fun. The latest QSoft Enterprise edition or one of Romex Software have a lot of nice functions allowing to auto backup the RAMdrive and load it back when you switch on and off your computer. Yes it might be lost if PC crash if you do not autobackup things, but this typically never happen, It is not for servers or critically important files but in its turn it is soooooo much faster and is eternal (well, lifetime guarantee) and no wearing off, TRIM, problems with compressed or 4K files.

    I do not know while similar board designs of RAMDrives as these two SSDs are not making its road to the world (with just the battery backups) – they are so much faster t yet

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    nice review. I like both of these companies, but I think you need to compare the iodrive II DUO if you really want to compare head to head what each manufacture would put against another. Another addition that would be nice is to see performance of actual work like indexed data using lucene. What is the performance gain on these working enviornments.

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    Sorry, but thinking this through HP should donate some equipment or Dell as well as updating the cards and also add tests of real applications to see performance gains. This was a great article none the less. Thank You

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    “Is there really a need for anything that fast?” with 4 dual GPUs being used for CUDA/OPenCl application you do need even more than what is being provided to keep the GPUs filled with data with bottleneck.

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