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 PRO'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 PRO's read speed. However, its average write speed dropped to 199.9 MB/s.
SanDisk Extreme PRO SSD - Dirty
To see how well the Extreme PRO could recover, I let the computer sit for about half an hour and then reran the test. Looking at the screenshot below, you can see that the drive's average writing speed jumped back up to 406.8 MB/s.
SanDisk Extreme PRO SSD - After Trim
Lastly, I used SanDisk's SSD Dashboard utility to perform a secure erase on the Extreme PRO. With the drive wiped clean, it had average read and write speeds of 446.3 MB/s and 402.4 MB/s, respectively.
SanDisk Extreme PRO SSD - Secure Erase
Final Thoughts:
SanDisk's Extreme PRO is a great choice for the gamer, enthusiast or media professional looking for an SSD that delivers consistent, pro-level performance and long term endurance. Building off the success of the award-winning Extreme II, the Extreme PRO combines Marvell's 88SS9187 controller with SanDisk's own 1Ynm eX2 ABL MLC Toggle NAND flash to deliver a fast and responsive storage experience. In our sequential read and write tests, the Extreme PRO was able to read at speeds as high as 560 MB/s and write at speeds in excess of 486 MB/s. Thanks to SanDisk's nCache Pro technology, it also did very well in our random write tests, producing more than 76,000 IOPS at low queue depths. Moreover, it performed equally well with compressible and incompressible data and was able to sustain these speeds, even after intensive use.
The SanDisk Extreme PRO is available now in 240GB, 480GB and 960G capacities. Prices on Amazon.com and Pricegrabber currently range from $179 up to $570, with the 480GB version reviewed here going for about $350.
Highs:
- Available in 240GB, 480GB and 960GB capacities
- Marvell 88SS9187 controller
- nCache Pro Technology
- Excellent sequential read and write speeds
- Good random read and write performance
- Performs equally well with compressible and incompressible data
- Consistent performance, even after intensive usage
- SATA 6Gb/s interface
- Toggle Mode NAND flash
- Large DRAM cache
- Supports TRIM, garbage collection and wear leveling
- Ultra-slim form factor
- Works with SanDisk's SSD Dashboard software
- 10 year warranty
Lows:
- Does not support hardware based encryption
- Pricey
