Intel RST3 Intel SSD Caching Feature for Z68 Chipset Explored

Intel plans to officially launch Z68 Express chipset on May 18th but you will be able to see reviews online from 12th onwards. Of course, those who can't wait for the official launch can already purchase the Gigabyte Z68X-UD7-B3 board from the retail market, first available in Taiwan and then the rest of the world in the coming weeks. Other brands like ASUS and ASRock are set to hit the retail next. Those enthusiasts hoping they can overclock their Sandy Bridge better on Z68 than the P67 will probably be disappointed but there is one important feature of Z68 that matters, and that is the SSD caching.

Intel RST3 Intel SSD Caching Feature for Z68 Chipset Explored

Intel plans to officially launch Z68 Express chipset on May 18th but you will be able to see reviews online from 12th onwards. Of course, those who can't wait for the official launch can already purchase the Gigabyte Z68X-UD7-B3 board from the retail market, first available in Taiwan and then the rest of the world in the coming weeks. Other brands like ASUS and ASRock are set to hit the retail next. Those enthusiasts hoping they can overclock their Sandy Bridge better on Z68 than the P67 will probably be disappointed but there is one important feature of Z68 that matters, and that is the SSD caching.

The SSD caching feature on the Z68 Express chipset is to be officially known as Intel Smart Response Technology which is one of the new feature of the Intel Rapid Storage Technology (RST) 10.5. This feature is unique only to Z68 which makes it stands out among the rest of the Cougar Point chipsets like P67 and H67. Intel Smart Response Technology basically allows you to use a SSD as a cache between the hard drive and memory. It provides a SSD-like system performance while having maximum storage capacity from the hard drives (single or RAID). Intel Smart Response Technology is implemented as a single drive letter solution so no additional drive letter is needed for the SSD.

Let's take a closer look at this neat feature, the requirements and its limitations.

System Requirements:

  • Z68 chipset
  • Intel Core processor
  • BIOS with the RST Smart Storage caching enabled
  • BIOS with SATA mode set to RAID enabled
  • BIOS that is PCI 3.0 and PMM (POST Memory Management) compliant to allow the OROM to handle dirty shutdowns of Accelerated disks/volumes
  • PMM must be able to allocate a minimum of 130MB of temporary, nonaligned, extended memory to the Legacy OROM
  • Intel RST 10.5 version release or later
  • “Cache SSD” must have 18.6GB minimum capacity. The max. cache size is 64GB so any capacity over 64GB will be used for user data
  • Only one ”Cache SSD” is allowed per computer system.

Feature Limitations:

  • A total of only one pass-through disk (RAID Ready system) or RAID volume can be 'Accelerated’ per computer system
  • Accelerated Volume criteria:

    • Accelerated RAID volumes are limited to 31.5TB or less
    • RAID levels 0, 1, 5, and 10 (No RRT volumes allowed to be accelerated)
    • All array member disks must be HDDs (No arrays with SSD member disks allowed to be accelerated)
  • No Acceleration of a RAID volume that is one of the volumes of a Matrix array (multiple volumes on a single array)
  • The SSD to be used as the “Cache SSD” must be attached to an internal SATA port of the computer

There are 3 Acceleration modes :

Mode Performance Dual Boot Safe Data Caching
Off No Acceleration N/A N/A

Enhanced
(Default)

Boot-time
Run-time reads
Paging
Yes Write-Through
Maximized
Boot-time
Run-time reads
Run-time writes
Paging
No Write-Back


Enhanced mode is the default acceleration mode as it offers data protection in the case of disk failure. It uses write-through data caching method to write data to the SSD and hard drive simultaneously. For user who wants maximum disk performance, you can choose the maximized mode but there is a high risk of data loss during disk failure. It uses the write-back cache method where data is written from the  Cache SSD to the disk at intervals. For even better disk performance, you can first stripe your hard drives then choose maximized mode. User can change acceleration mode at any time as long as the SSD and hard drive are working normally.