Intel is set to officially launch its Z68 Express chipset on May 18th. So what has this got to do with being on topic with SSDFreaks.com? Well, what makes the Z68 special is its SSD caching feature, officially known as Intel Smart Response Technology and one of the new features of Rapid Storage Technology (RST) 10.5.
Smart Response Technology works by providing SSD-like performance from a hard disk or RAID array by using an attached SSD of up to 64GB as a cache for read (and write) operations. The technology works similar to Seagate’s hybrid hard disk, but in this case the user can choose their own single hard disk or group of hard disks in a RAID array and a separate SSD to for the cache. The Z68 chipset handles the caching operations and the OS sees a single drive volume as with a dedicated hybrid hard disk.
For the caching to work, the SSD must have a capacity of at least 18.6GB and the cache can be up to 64GB. If the SSD is larger than 64GB, the remaining capacity can be used for user data. Only a single SSD can be used for the cache, which can be used to accelerate either a single hard disk or a RAID array that has been configured in RAID level 0, 1, 5 or 10. The SSD cache cannot be used to accelerate another SSD or a RAID array containing any member SSDs.
Like a RAM cache, when the SSD cache is enabled, it can be run in either write-through or write-back mode. In write-through mode, it accelerates read operations such as speeding up the boot process, application launches and page file performance. Data is written to both the SSD and hard drive or RAID array being accelerated simultaneously. In the write-back mode, the data is written to the SSD first to speed up write operations and then written to the hard drive or RAID array in the background at intervals. The write-back mode has a high risk of data loss in the event of a drive failing and is not safe for use in a dual-boot configuration.