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 fix 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 Gold S31'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. Looking at the screenshot below, you can see that the Gold S31's average read and write speeds dropped to 149.7 MB/s and 146.2 MB/s, respectively.
SK hynix Gold S31 - Dirty
To see how well the Gold S31 could recover, I let the computer sit for about 30 minutes and then reran the test. The drive wasn't able to reach the factory fresh performance shown in our earlier tests. However, its average write speed jumped up to 375.8 MB/s.
SK hynix Gold S31 - After Trim
Lastly, I used Parted Magic to perform a secure erase on the Gold S31. With the drive wiped clean, it had average read and write speeds of 444.1 MB/s and 398.9 MB/s, respectively.
SK hynix Gold S31 - Secure Erase
Final Thoughts:
The Gold S31 is the first SSD from SK hynix to come through the 'Labs and to be honest, they could not have made a better first impression. Designed and built entirely in-house, this consumer-oriented drive combines the company's own "Quartz" controller with their 72-layer 3D TLC NAND flash to deliver performance, quality and reliability at a competitive price. In our sequential read and write tests, the 1TB version of the Gold S31 was able to read at speeds as high as 563 MB/s and write at speeds in excess of 492 MB/s. It also had no problems holding its own in our random write tests, producing more than 81,000 IOPS at low queue depths.
Currently, the Gold S31 is offered exclusively through Amazon. Prices start at $50 for the 250GB drive and go up to $119 for the 1TB version reviewed here. SK hynix expects to offer the Gold S31 to other North American and European markets starting next year.
Highs:
- Available in 250GB, 500GB and 1TB capacities
- Equipped with 72-layer 3D TLC NAND
- Good sequential and random read and write performance
- Ultra-slim design
- Reasonably priced
- 5 year warranty
Lows:
- Does not support hardware based encryption
- Limited availability
