Two drives. Double the performance. That's ultimately what we were looking for from this pair of 40GB SSDs. But can the G.Skill Phoenix Pros deliver? Sometimes. As a single drive, the G.Skill Phoenix Pro is in line with expectations given that it's a bang up to date drive based on our favourite SSD controller. As an all-round performance proposition, it's about as good as it gets.

Its sequential read and write throughput of 284MB/s and 271MB/s respectively, and random write performance of 54MB/s make it competitive. It's no slouch in our real-world application tests either, even if it is a little slower in our application install test than we expect from a SandForce-powered drive.

Where things get really interesting is in RAID 0 configuration. RAID 0 involves striping data across the two SSDs to create a single, larger data volume. Theoretically, performance also improves because the drives can be written to and read from simultaneously. By contrast, a RAID 1 array mirrors data on the drives, increasing reliability.

Going by several of our benchmarks results, these drives do exactly what it says on the RAID 0 tin. Sequential read and write performance effectively doubles to 572MB/s and 534MB/s. As if those numbers weren't staggering enough, the 2,280MB/s result in the HDTach Burst test is simply out of this world. However, these don't accurately reflect real-world performance. But it does confirm that when it comes to RAID 0, one plus one sometimes adds up to more than two.

Of course, the maths can work the other way, too. The G.Skill Phoenix Pros in RAID 0 deliver very little additional performance over a single drive in the random write test. But what about the tests that matter most, the real application benchmarks?

The answer is mixed. Decompressing a 1GB zip file drops from 35 seconds for the single drive to 30 seconds in RAID 0. Meanwhile, the time taken to install a 1.5GB application tumbles from 42 seconds to just 26 seconds. If that sounds impressive, it's worth noting that the single drive rather underperformed in the application installation test.

Performance concerns aside for a moment, it's worth noting that the Phoenix Pros make a good impression thanks to their quality brushed alloy enclosures and bundled 2.5-inch-to-3.5-inch drive bay adapters.

We liked

SandForce's SF-1200 has been our favourite SSD controller for some six months and G.Skill's new SSD certainly backs up that positive impression. It's a seriously quick little SSD. Strap two of them together and the results, at least some of the time, are stunning.

We disliked

£90-plus for a 40GB drive is a painful proposition. Buying two of them for double the price doesn't really provide relief, even if the result is a more usable overall data volume and increased performance. Partly that's because you're still left with a pretty puny amount storage. But it's also because the real-world benefits of the RAID 0 configuration are often modest.

Verdict

Given the mixed real-world benefits of a RAID config, there's better value to be had from larger SSDs.

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