Results: PCMark 8 Storage Consistency Test
PCMark 8's Storage Consistency test is fast becoming my favorite canned benchmark. Usually, that's code for lazy benchmarking. But the folks at Futuremark really came up with something stellar using PCMark 8's real-world workloads. What we end up with are trace-based tests played back to back, with specific conditioning that happens prior to each round. I've gone into a lot of depth on this in past reviews, so if you'd like to know more, I invite you to go back and read the background page.
PCMark 8 Storage Consistency Test: Bandwidth
PCMark 8's Adobe Photoshop (Heavy) trace is far and away the most intensive of the trace bundle. That's why we use it to show latency and bandwidth data for each of the 18 constituent rounds.
I'll let you guess which line on the graph represents Samsung's XP941.
Have you figured it out yet? Here's a hint: it's the fastest one. And not by a small amount, either. The XP941 serves up a benchmark-setting 700 MB/s in the recovery rounds. It dips as low as 500 MB/s in the debilitating degrade phase, which is simply unheard of. Even attached to the Z97 PCH's two-lane M.2 slot, it's still intensely quick. There's just a less capable interface supporting it.
Samsung's XP941 is as much as 20x faster than some of the quickest 6 Gb/s SSDs in this particular trace from this particular benchmark (that is to say our results don't necessarily map over to other workloads). It's hard to overlook the crushing defeat Plextor's M6e (in purple) and Samsung's own 840 EVO (in orange) sustain at the hands of this M.2 drive.
Despite my skepticism of AHCI-based PCIe storage, Samsung at least shows its XP941 to be an exception to the rule.
And here are the overall scores, showing the best and worst scores across PCMark 8's 18 rounds. No surprise, Samsung's XP941 owns the top tier. ASRock's Ultra M.2 slot hosting Samsung M.2 drive pushes as high as 5016 PCMarks. Attached to the PCH's M.2 interface, it registers a score of 4999.