We’ve said before in the past that the rise of the SSD as a replacement to the conventional mechanical drive is inevitable, but still some way off. Affordable SSDs might have the performance in the read stakes, but their poor JMicron drive controllers have so far proved disappointing when you look at write performance, and while Intel’s X25 series of SSDs are able to produce excellent read and write speeds their price is extremely prohibitive.
Capacities are also an obstacle for the humble SSD, and while they’re able to provide high performance across the entire drive (unlike a mechanical disk where performance drops off the closer the read/write heads get to the centre of the disk) the capacity of a high mechanical drive is many times that of an SSD, especially with the imminent arrival of 2TB drives!
However, the G.Skill Titan looks to go some way toward addressing both these issues. Packing in 256GB of MLC Flash storage it’s one of the largest SSDs publicly available and although it's based on the cheaper JMicron Controller, it employs some hardware trickery to offer significantly faster read and write times than the 128GB G.Skill SSD we looked at back in December.
Click to enlarge
While still using the same 2.5” black metal casing as the 128GB model, cracking the Titan open reveals an ingenious approach to improving performance without having to develop a completely new drive controller or architecture.
The 256GB of MLC memory is split between 32 separate 8GB Samsung “846” NAND flash modules, which have been double stacked on both sides of the PCB to save on space within the casing. These 32 modules are then evenly divided between the Titan’s dual JMF 602 drive controllers, which are in turn connected to a JMB390 SATA multiplier.
The result is reminiscent of a RAID0 array, with each drive controller connected to 128GB of MLC NAND flash and the two combining via the SATA multiplier to produce a 256GB SSD that’s much faster than a solitary 128GB drive. Unlike a RAID0 array though, data is not uniformly striped across the drive - entire files can be written to specific cells. While the result, just as with RAID, will unlikely double the drive’s performance, it should provide a significant improvement in both read and write speed, with G.Skill quoting peak performance of 200MB/s read and 160MB/s write.
Click to enlarge - the drive is equipped with two drive controllers in a RAID0 like array
However, the use of the same memory modules and drive controller as the previous G.Skill 128GB drive is a concern, with the key issue of micro stuttering, where the drive receives simply too many commands for it to function properly still a large concern. Whether the use of two drive controllers is able to alleviate the problem is something we’ll be looking at closely.
Price is, as always with SSDs, also a sticking point - the 256GB version of the Titan currently available in the USA for a whopping $499. While this is less than twice that of the 128GB model, which retails for $299, it’s still enough to buy no less than five Samsung Spinpoint F1 1TB hard disk drives – enough to build a very meaty RAID5 array.
Can the Titan justify its price, and how will the use of dual drive controller chips affect performance? Let’s find out.