OCZ Vector 256GB review

Solid-state drive controller chipsets matter. A lot. That's why relatively small outfit OCZ acquired boutique controller manufacturer Indilinx with a view to making its own kit.

But controller chipsets are also bloody difficult to get right, which is why Intel was forced to buy Sandforce controllers off the shelf when its own technology had fallen behind. But if Intel, with its bottomless pit of money, can't get it right, what hope for OCZ?

It's time to find out, courtesy of the new OCZ Vector - the first OCZ drive to have a truly home-grown controller chipset. Yes, really.

Previous OCZ drives like the Vertex 4 were branded as 'Indilinx Infused', but the Indilinx Everest 2 controller was in reality just re-badged Marvell silicon with custom firmware. Admittedly firmware is a very important part of the controller chipset package, but if you're not designing custom hardware, you can't truly claim to be cooking up the real in-house deal.

But never mind, because that's finally arrived with the Vector SSD and its Barefoot 3 controller. As ever, full technical details of the chip's internal architecture are hard to come by: manufacturers simply don't release deep-dive data in the same way that CPU makers do.

For the most part though, that makes sense - knowing how the innards of a CPU work can be important for software developers, whereas digging around in the oily bits of an SSD is rather more academic. Still, what do we know?

Well, there's an ARM Cortex CPU core in there, but the exact model isn't divulged. Frankly, that could mean anything from a fairly simple in-order effort to one of ARM's snazzy new out-oforder designs, though we suspect something along the lines of Cortex A8 is probably about as fancy as it gets.

Intriguingly, there's another co-processor core to go along with the ARM Cortex core. OCZ calls this Aragon, but we know even less about that than we do the non-specific ARM Cortex core.

At this stage, the penny will have dropped that discussions of controller chip specifications can be pretty frustrating. Instead, we have to look to other specifications to get a feel for what it's capable of.

Specifics

The key benchmark here, of course, is OCZ's own Vertex 4 with its Everest 2 controller. Keeping things like-for-like and comparing the 256GB models, peak read speeds for the new Vector drive actually drop by 10MB/s to 550MB/s, but claimed write speeds are up 20MB/s to 530MB/s.

If that seem incremental, going on insignificant, bear in mind that numbers above 500MB/s for peak throughput are hammering up against the maximum capabilities of the SATA6Gbps interface. You'll never see a single SATA6Gbps drive capable of data rates of 600MB/s and beyond.

Similarly, it's often not peak sequential performance that defines how fast a drive feels in practice. Instead, random access performance is usually more critical for the sort of daily drive churn generated by modern PCs. Happily, then, OCZ claims that 4k random IOPS performance is up all round.

Read IOPs step up to 100,000 from 90,000, and writes grow from 85,000 to 95,000. The Vertex 4's numbers were already very beefy in those areas, so the Vector really does look pretty impressive on paper.

But what about the rest of the hardware? In terms of the main memory, we're talking 256GB of MLC two-bit-per-cell flash. It's 25nm NAND produced in partnership by Intel and Micron, it's synchronous, and it's basically the good stuff.

In fact, it's good enough in combination with whatever wear-levelling algorithms OCZ has come up with for a warranty lasting five years or 36.5TB of writes (whichever comes first). If you're wondering what the latter translates to in reality, it's 20GB of writes each and every day for five years.

For the vast majority of users, the five-year timer will expire before the write budget is soaked up. That's impressive stuff, but it's particularly critical for OCZ, because if there's one area where its drives have fallen short historically, it's reliability. An effective five-year warranty gives you a very healthy window of operation. Even if it's still working perfectly in five years' time, odds are you'll be ready to upgrade by then anyway.

With the Vector, OCZ also continues to offer firmware with a performance mode that gives increased throughput as long as less than 50 per cent of the drive's capacity is used. Put it all together and you certainly have one hell of a package on paper, but does it truly deliver in practice?

Delivery report

In nearly all of our benchmarks, the answer has to be a resounding yes. This drive is clearly faster than its Vertex 4 predecessor in every metric except 4k random reads, where it's a dead heat, but how does it stack up compared to the current champ of SSDs, Samsung's 840 Pro? The answer is, it's very, very tight.

They trade blows in the sequential read and write test for both compressible and incompressible throughput. All the results are up around the 500MB/s mark, and some are so similar, odds are these two drives are realistically just bumping up against the limitations of the SATA6Gbps interface.

Things get a little more interesting in the 4k random benchmarks, an area where there's still plenty of scope for drives to flex their muscles. Here the Samsung has the edge for reads with 28MB/s compared with 23MB/s for the new Vector, but for writes OCZ absolutely blows Samsung away. It's 74MB/s versus 59MB/s.

Then there's our 1GB ZIP file decompression test where the Vector clocks our fastest time ever at 23 seconds. That's a particularly nice result given that the ZIP file decompression is a bona fide real world test of drive performance, not just a synthetic measure of theoretical throughput.

Benchmarks

Sequential read performance
AS SSD: Megabytes per second: Bigger is better
OCZ VECTOR 256GB: 514
OCZ VERTEX 4 256GB: 466
SAMSUNG 840 PRO 256GB: 516
INTEL SSD 520 240GB: 494

Sequential write performance
AS SSD: Megabytes per second: Bigger is better
OCZ VECTOR 256GB: 494
OCZ VERTEX 4 256GB: 454
SAMSUNG 840 PRO 256GB: 498
INTEL SSD 520 240GB: 290

4K random read performance
AS SSD: Megabytes per second: Bigger is better
OCZ VECTOR 256GB: 23
OCZ VERTEX 4 256GB: 23
SAMSUNG 840 PRO 256GB: 28
INTEL SSD 520 240GB: 20

4K random write performance
AS SSD: Megabytes per second: Bigger is better
OCZ VECTOR 256GB: 74
OCZ VERTEX 4 256GB: 70
SAMSUNG 840 PRO 256GB: 59
INTEL SSD 520 240GB: 50

ZIP file decompression performance
ZIP: Seconds: Quicker is better
OCZ VECTOR 256GB: 23
OCZ VERTEX 4 256GB: 26
SAMSUNG 840 PRO 256GB: 26
INTEL SSD 520 240GB: 25

Test of time

Put all our results together and you have to conclude that the Vector might just be the fastest SSD on the market right now. It's certainly not materially any slower than the Samsung 840 Pro.

Whether it will prove as reliable is another matter. With any new SSD, there are always doubts regarding both outright longevity and the manner in which performance holds up over time and with heavy world loads. But that five-year warranty at least suggests OCZ has confidence in the Vector's staying power and we had zero problems in testing.

The only major downside is that the Vector is burdened with a £197 price tag. Admittedly, other premium performance drives are priced in roughly the same ballpark (Samsung's 840 Pro goes for around £190 in 256GB), but if anything, we'd like to see OCZ pricing the Vector below the 840 Pro.

After all, Samsung's drive has a great reputation for both performance and reliability. Rolling the dice with OCZ would be a lot more attractive with some financial incentive too.