SanDisk Extreme 240GB Solid State Drive

While not yet a major player in the SSD market, SanDisk is very optimistic about its success in this area. The company expects 2012 to be a big year for SSDs and is expanding its presence in the OEM, enterprise and retail channels. To tap into the growing consumer SSD market, SanDisk recently launched the Extreme. Designed with enthusiasts and gamers in mind, this high-performance SSD is powered by LSI's SandForce SF-2281 processor and features a SATA 6GB/s interface, native TRIM support and DuraClass technology. The Extreme also uses a custom firmware and SanDisk's own 24nm MLC Toggle Mode NAND flash to deliver up to 555MB/s read and 520MB/s write speeds for fast boot times and application launches.

The Extreme is available in 120GB, 240GB and 480GB capacities. For this review, SanDisk sent us the 240GB version of the drive which is capable of delivering up to 555 MB/s sequential read and 520 MB/s sequential write speeds as well as up to 39,000 random read and 83,000 random write IOPS.

With store shelves already full of "SandForce Driven" SSDs with similar specs and features, the Extreme is up against some stiff competition. To give you an idea of what to expect, we'll take a closer look at SanDisk's new SSD and then put it through its paces to see how it performs. Does the Extreme have what it takes? Can it deliver the performance we've come to expect from SanDisk? Keep reading as we find out.

The Extreme comes in a small, black box. While there aren't a lot of details on the back, the front advertises key features like the drive's 240GB capacity and SATA 6Gbps interface as well as some of the advantages of a solid state drive.

SanDisk doesn't include a lot of extras with the Extreme. Aside from the SSD, the only other thing in the box is a small, fold out guide that contains warranty information as well as installation instructions for both desktop and notebook computers.

Physical Features:

The Extreme looks very similar to SanDisk's Ultra series SSDs. The drive's outer casing is made entirely out of metal and is covered by a durable, matte black finish. There is also a large, black and red sticker showing that the SSD is part of SanDisk's Extreme series.

As I mentioned earlier, the Extreme uses LSI's SandForce SF-2281 controller chip. The SF-2281 can be found in a number of other SSD's including the ADATA S511, Corsair Force Series 3, OWC Mercury 6G, Kingston HyperX, OCZ Vertex 3 and Patriot Pyro SE.

For the Extreme, SanDisk opted to use their own 32GB 24nm (05091 032G) MLC Toggle Mode NAND flash chips. Looking at the pictures above, you can see that the 240GB version of the drive has four of these chips on either side of the PCB. If you do the math, you'll see that this equals 256GB and not the 240GB of storage the drive advertises. The SandForce controller uses this extra 7% (16GB) to maximize read and write performance and extend the endurance and overall reliability of the drive.

The test system used in this review was an HP 8200 Elite. The computer came equipped with an Intel Core i5-2400 CPU, 4GB of DDR3 1333MHz memory, Seagate Barracuda 7200.12 ST3250312AS 250GB SATA 6 Gb/s hard drive, NVIDIA Quadro FX580 512MB PCIe graphics card and an Intel 82579-LM gigabit network card. For the operating system, I installed a fresh copy of Windows 7 Enterprise.

To test the performance of the SanDisk Extreme SSD, I ran a series of benchmarks using CrystalDiskMark 3.0.1, HD Tach RW 3.0.4.0, ATTO Disk Benchmark 2.46, AS SSD, HD Tune Pro 4.61 and Iometer. For comparison, I've also included test results from the Samsung 830 SSD, Plextor PX-256M3S, Patriot Pyro SE, Plextor PX-256M2P, Kingston HyperX, OCZ Vertex 3 and OCZ Agility 3.

As I mentioned earlier, the Extreme is based on SandForce's SF-2281 controller. Like other SandForce controllers, the SF-2281 features a technology called DuraWrite, which uses data compression to lower write amplification and extend the life of the drive by reducing the number of program-erase cycles. This data compression also plays a big part in the controller's performance. The more the data can be compressed, the faster an SSD like the Extreme is able to read and write. Looking at the screenshot above, you can see that there is a considerable performance difference when writing incompressible (0%) and compressible (100%) data. However, thanks to the Extreme's MLC Toggle Mode NAND, its read speeds aren't affected nearly as much.

CrystalDiskMark 3.0.1:

First, I ran a few quick tests using CrystalDiskMark. This benchmark tool measures the performance of a storage device by testing its sequential read and write speeds as well as its random read and write speeds using blocks 512K and 4K in size.

SanDisk Extreme SSD 240GB

Patriot Pyro SE 240GB

According to SanDisk, the 240GB Extreme is capable of reading at 550MB/s and writing at 520MB/s when connected to a SATA 6 Gb/s port. The drive didn't come close to these numbers using CrystalDiskMark's default (random) test data. However, with the highly compressible 0x00 (0 Fill) data, the Extreme was able to read at 483.1 MB/s and write at 456.7 MB/s.

SanDisk Extreme SSD 240GB - All 0x00, 0Fill

Patriot Pyro SE 240GB - All 0x00, 0Fill

HD Tach RW 3.0.4.0:

Next, I used HD Tach to test the Extreme's read, write and burst speeds as well as its seek times and CPU usage.

Looking at the screenshot above, you can see that the Extreme had average read and write speeds of 362.4 MB/s and 352.8 MB/s respectively, as well as a burst speed of 341.9 MB/s.

ATTO Disk Benchmark 2.46:

I also used ATTO Disk Benchmark to test the Extreme's sequential read and write speeds. The tests are run using blocks ranging in size from 0.5KB to 8192KB and the total length set to 256MB.

SanDisk Extreme SSD 240GB

Patriot Pyro SE 240GB

When tested with ATTO, the Extreme's read speeds topped out at 555 MB/s and its write speeds at nearly 496 MB/s.

AS SSD:

AS SSD is a relatively new benchmark designed specifically for solid state drives. The application contains five synthetic tests used to determine the sequential and random read and write performance of a drive.

AS SSD also includes a copy benchmark. This test copies an ISO (two large files), program (many small files) and game (small and large files), returning the speed and duration of each.

HD Tune Pro 4.61:

Next, I ran a series of tests using HD Tune Pro. This hard disk utility measures a drive's performance by testing its sequential read and write speeds as well as its access time, burst rate and CPU usage. For this review, I'm also going to use it to benchmark the Extreme's random read and write speeds, random access times and the number of operations per second.

SanDisk Extreme 240GB - HD Tune Read Benchmark

Patriot Pyro SE 240GB - HD Tune Read Benchmark

SanDisk Extreme 240GB - HD Tune Write Benchmark

Patriot Pyro SE 240GB - HD Tune Write Benchmark

The Extreme performed very well when benchmarked with HD Tune. The drive had average read and write speeds of 484.9 MB/s and 423.4 MB/s, respectively, and a burst rate of 317.8 MB/s when reading.   

SanDisk Extreme 240GB - HD Tune Random Access Read

Patriot Pyro SE 240GB - HD Tune Random Access Read

SanDisk Extreme 240GB - HD Tune Random Access Write

Patriot Pyro SE 240GB - HD Tune Random Access Write

The Extreme didn't disappoint when doing random reads and writes. When reading 4KB blocks, the drive reached 16337 IOPS and had an average speed of 63.975 MB/s. The Extreme was even faster when writing, reaching 18985 IOPS with an average speed of 74.162 MB/s.

Iometer:

Lastly, I ran a series of tests using Iometer. This tool can be configured to benchmark a number of things. In this case, I used it to measure the Extreme's read and write speeds and the number of operations per second. The tests were run using random bytes and a queue depth of 3.

The Extreme's performance was very similar to what we saw in our other tests. With highly compressible, repeating data, the drive was able to read at 524.07 MB/s and write at 476.93 MB/s. With its Toggle Mode NAND flash, the Extreme did not slow nearly as much as the OCZ Agility 3 when reading random data. However, its write speeds dropped to 275.9 MB/s. 

The Extreme performed very well when doing random reads and writes. With repeating data, the drive was able to read at 67.79 MB/s and write at a blazing 296.64 MB/s. Here too, the Extreme took a performance hit when tested with random data. However, it was still able to write at 174.69 MB/s.

According to SanDisk, the Extreme can deliver a maximum of 83,000 IOPS when randomly writing 4K blocks. In our tests, the drive reached 75,940 IOPS with repeating data and 44,721 IOPS with random data.

TRIM Performance:

While SSDs offer many benefits, there are some downsides to using flash memory. One of the biggest issues people run into is performance degradation. Over time, an SSD will run out of fresh blocks and will have to write over data the file system has marked as deleted. This procedure is very complicated and can slow an SSD's write speeds considerably.

To address this problem, most manufacturers have added TRIM support to their SSDs. The TRIM command allows an operating system, such as Windows 7, to tell an SSD which data blocks are no longer in use. Using this information, the drive pro-actively erases these blocks and adds them to the free block pool.

To test the Extreme's TRIM function, I first put the drive in a "dirty" state. I used Iometer to fill the entire drive and then ran a random write test for 30 minutes. This had very little effect on the Extreme's write speed. However, its average read speed dropped to 203.8 MB/s.

SanDisk Extreme SSD - Dirty

To see how well the Extreme could recover, I let the computer sit for a few hours and then reran the test. The drive wasn't able to reach the factory fresh performance shown in our earlier tests. However, its average read speed climbed up to 301.1 MB/s.

SanDisk Extreme SSD - After Trim

Lastly, I used Parted Magic to perform a secure erase on the Extreme. With the drive wiped clean, its read speed jumped back up to 365.8 MB/s.

SanDisk Extreme SSD - Wiped

Final Thoughts:

With the Extreme, SanDisk has made its long awaited entrance into the high-performance SSD market. Targeted at gamers and enthusiasts, this new SSD combines LSI's SandForce SF-2281 controller with the company's own 24nm MLC Toggle Mode NAND flash to deliver some truly impressive performance. In our sequential read and write tests, the Extreme was able to read at speeds as high as 555 MB/s and write at speeds in excess of 475 MB/s. It also took the top spot in our random write tests, producing more than 75,000 IOPS. As with other SandForce drives, the Extreme's performance did take a hit when reading and writing incompressible data. However, thanks to its Toggle Mode NAND flash, its performance didn't suffer nearly as much as some other drives.

The SanDisk Extreme SSD is available now in 120GB and 240GB capacities and a 480GB version is coming later this year. The 120GB drive currently retails for about $150 with the 240GB version reviewed here going for less than $330 on Amazon.

Highs:

• Available in 120GB, 240GB and 480GB capacities
• SandForce SF-2281 processor with DuraClass, DuraWrite and RAISE technologies
• Excellent sequential read and write speeds
• SATA 6Gb/s interface
• Toggle Mode NAND flash
• Supports TRIM, SMART and NCQ
• Well constructed
• Reasonably priced
• 3 year warranty

Lows:

• Does not include a 2.5" to 3.5" adapter bracket
• Not as fast when writing incompressible data