As enterprise SSDs become more specialized and application-focused, Intel is hoping its SSD DC S3500 will strike a chord with customers looking for excellent read performance on a budget. We compare this drive to other notable contenders in its class.
This may come as a surprise to enthusiasts focused on cutting-edge consumer drives, but the 3 Gb/ss Intel SSD 320 family is still incredibly popular in the enterprise. Even though it's only two years old, though, the architecture's performance has not aged gracefully. A quick rundown of its four-corner specifications tells a sad story:
- Sequential Reads: 270 MB/s
- Sequential Writes: 200 MB/s
- Random Reads (100% Span): 39,500 IOPS
- Random Writes (100% Span): 400 IOPS
Wait, what? Yeah, you read that correctly. Four hundred IOPS for 4 KB random writes across all LBAs at a queue depth of 32. So why in the world are IT professionals not only buying these drives still, but buying them in the thousands of units? The answer isn't as straightforward. Even though the 320's performance isn't particularly impressive, the series covers the rest of its bases fairly well. Once Intel worked out its firmware issues, the SSD 320s became solid and reliable workhorses, and we've heard many anecdotal stories from large corporations about their reliability.
The SSD 320s clearly suffered an unfortunate identity disorder, too. Was it an enterprise drive or something intended for consumers? It had power loss protection and full-disk encryption, so it must be business-class hardware, right? At the same time, it replaced the X25-M, so surely it was intended for enthusiasts. In reality, it was a bit of both. You just had to do some reading in order to figure that out.
Intel spent the last two years trying to sort out its product channels. It's telling a clearer story now than even a year ago. And now enterprise customers are getting a true replacement for the SSD 320s in its SSD DC S3500. There is no confusing the issue on this one; it's business-oriented through and through. The DC stands for data center, so it sort of has to be.
The SSD DC S3500 is targeted mainly at read-intensive and mixed-workload applications. Anything more write-heavy is kicked up to the SSD DC S3700 (Intel SSD DC S3700 Review: Benchmarking Consistency). A few short months ago, when a big business wanted storage for the sort of role the S3500 is designed to fill, they were limited to consumer drives. However, since the start of the year, we've seen Seagate launch the 600 Pro (Seagate 600 Pro-Series 200 GB SSD Review: For The Enterprise) and Samsung introduce its 843. Along with the SSD DC S3500, we see those drives nosing out the desktop-oriented SSDs from enterprise rotation.
Intel's latest entry comes with all of the bells and whistles expected from a pricier enterprise drive. You get end-to-end data protection, power loss protection, 256-bit AES encryption, ECC memory, a 2 million hour MTBF, and a five-year warranty. It's good to see Intel integrate all of that reliability-boosting technology, considering this is still an entry-level offering wish pricing not much higher than the desktop-class stuff we typically review.
Most SSD manufacturers give you a handful of options when it comes to configuring solid-state storage. With Intel, that's an understatement. In the 7 mm, 2.5" form factor, you can pick between 80, 120, 160, 240, 300, 480, 600, and 800 GB capacities. In the 5 mm, 1.8" form factor, there are 80, 240, 400, and 800 GB models. This wide range of choices lets Intel target applications ranging from industrial embedded to data centers to blade servers.
Unlike many enterprise SSD manufacturers, Intel always discloses pricing information up-front. While we don't have MSRPs for every capacity point, we do know that the 480 GB model we're reviewing should run around $579. At ~$1.20/GB, Intel is quite competitive next to the other read-focused enterprise SSDs. When you take into account the warranty and reliability-focused features, you might even be tempted to snag one for your next desktop build. Before we go down that path, though, let's look at the specs.
| Intel SSD DC S3500 Line-Up | ||||||||
|---|---|---|---|---|---|---|---|---|
| User Capacity (GB) | 80 | 120 | 160 | 240 | 300 | 480 | 600 | 800 |
| Interface | 2.5" 6 Gb/s SATA | |||||||
| Sequential Read (MB/s) | 340 | 445 | 475 | 500 | 500 | 500 | 500 | 500 |
| Sequential Write (MB/s) | 100 | 135 | 175 | 260 | 315 | 380 | 410 | 450 |
| 4K Random Read (IOPS) | 70,000 | 75,000 | ||||||
| 4K Random Write (IOPS) | 7,000 | 4,600 | 7,500 | 9,000 | 11,000 | 11,500 | ||
| Power Consumption (Active) | 1.8 W | 2.0 W | 2.3 W | 2.9 W | 3.5 W | 4.3 W | 4.5 W | 5 W |
| Power Consumption (Idle) | 0.6 W | |||||||
| Write Endurance (TBW) | 45 | 70 | 100 | 140 | 170 | 275 | 330 | 450 |
Inside Intel's SSD DC S3500
If you've already read Intel SSD DC S3700 Review: Benchmarking Consistency, then you might want to skip ahead. The SSD DC S3500 and S3700 don't just share a few similarities; they share almost every single component. Starting on the exterior, they employ the same aluminum enclosure, right down to the part number. Can you tell which is which?
As with the S3700, we see two through-hole 35 V 47 uF capacitors notched into the edges of the PCB.
On the inside, we see three black, plastic stand-offs covering each of the screw holes. It's easy to observe that the PCB is identical to the one found on Intel's SSD DC S3700. Even the reference designators on the silk screen match. Both SSD DC S3000 families utilize the same PC29AS21CA0 controller, too. This Intel-developed, eight-channel, 6 Gb/s processors performed well in our S3700 review, exhibiting excellent consistency.
Next, we take note of two DDR3-1600 DRAM packages from Micron (MT41K512M8RA-125). Each FBGA module hosts 512 MB of memory, totaling 1 GB of cache on the SSD.
Up until now, the only difference between both drive families was the DRAM they use for cache. But with the SSD DC S3500, Intel is replacing the 25 nm HET-MLC found in the S3700 with 20 nm MLC. This is what gives Intel the ability to hit lower price points with its SSD DC S3500. And as we'll see shortly, it's also the reason why write endurance is so much lower.
As with the SSD DC S3700, some capacities of the S3500 have an odd assortment of NAND packages. The 480 GB version we have in the lab leverages fourteen 32 GB modules, one 64 GB module, and one 16 GB module. That adds up to 528 GB, yielding 9% over-provisioning. And that's substantially less than the SSD DC S3700 at ~22%.
Test Setup, Benchmarks, And Methodology
| Test Hardware | |
|---|---|
| Processor | Intel Core i7-3960X (Sandy Bridge-E), 32 nm, 3.3 GHz, LGA 2011, 15 MB Shared L3, Turbo Boost Enabled |
| Motherboard | Intel DX79SI, X79 Express |
| Memory | G.Skill Ripjaws Z-Series (4 x 4 GB) DDR3-1600 @ DDR3-1600, 1.5 V |
| System Drive | Intel SSD 320 160 GB SATA 3Gb/s |
| Tested Drives | Intel SSD DC S3500, 480 GB |
| Graphics | AMD FirePro V4800 1 GB |
| Power Supply | OCZ ModXStream Pro 700 W |
| System Software and Drivers | |
| Operating System | Windows 7 x64 Ultimate |
| DirectX | DirectX 11 |
| Driver | Graphics: ATI 8.883 |
| Benchmark Suite | |
| Iometer v1.1.0 | 4 Workers, 4 KB Random: LBA=Full, Span Varying Queue Depths |
| ATTO | v2.4.7, 2 GB, QD=4 |
| Custom | C++, 8 MB Sequential, QD=4 |
| Enterprise Testing: Iometer Workloads | Read | Write | 512 Bytes | 1 KB | 2 KB | 4 KB | 8 KB | 16 KB | 32 KB | 64 KB | 128 KB | 512 KB |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Database | 67% | 100% | n/a | n/a | n/a | n/a | 100% | n/a | n/a | n/a | n/a | n/a |
| File Server | 80% | 100% | 10% | 5% | 5% | 60% | 2% | 4% | 4% | 10% | n/a | n/a |
| Web Server | 100% | 100% | 22% | 15% | 8% | 23% | 15% | 2% | 6% | 7% | 1% | 1% |
The Storage Networking Industry Association (SNIA), a working group made up of SSD, flash, and controller vendors, has a testing procedure that attempts to control as many of the variables inherent to SSDs as possible. SNIA’s Solid State Storage Performance Test Specification (SSS PTS) is a great resource for enterprise SSD testing. The procedure does not define what tests should be run, but rather the way in which they are run. This workflow is broken down into four parts:
- Purge: Purging puts the drive at a known starting point. For SSDs, this normally means Secure Erase.
- Workload-Independent Preconditioning: A prescribed workload that is unrelated to the test workload.
- Workload-Based Preconditioning: The actual test workload (4 KB random, 128 KB sequential, and so on), which pushes the drive towards a steady state.
- Steady State: The point at which the drive’s performance is no longer changing for the variable being tracked.
These steps are critical when testing SSDs. It’s incredibly easy to not fully condition the drive and still observe out-of-box behavior, which may lead one to think that it’s steady-state. These steps are also important when going between random and sequential writes.
For all performance tests in this review, the SSS PTS was followed to ensure accurate and repeatable results.
All tests employ random data, when available. Intel's SSD DC S3500 does not perform any data compression prior to writing, so there is no difference in performance-based data patterns.
