Solid State Drives (SSD’s) have become a very desirable addition to any desktop PC or laptop computer. The reason is their speed, boot up times and data read and write are ridiculously fast compared with the traditional hard disk drive. But the price per GB for Solid State drives are much higher than that of the hard disk drive as well as total storage sizes are much bigger in the traditional drives as well. This means that there is still a place for the HDD is most PC’s and that is for bulk storage.
This has lead many PC manufacturers and home system builders to include both a standard Hard Disk Drive and a Solid State Drive in their PC builds, this is fine but it means that you need two pieces of hardware for storage taking two lots of power and requiring two sets of cabling. Not a huge problem I’m sure you will admit but it isn’t an ideal solution. The best as we know would be to store everything on the NAND flash SSD but this is too expensive, so the SSHD is born.
There are two types of SSHD one is a true SSHD and the other while referred to as an SSHD is really properly described as just a hybrid drive, lets start with that. The hybrid drive is like having a hard disk and an SSD encased in the same housing. This requires only only power source but the PC will treat them as two separate drives with two separate drive letters. For all intense and purpose they are separate disk drives. Standard procedure here would be to install the operating system onto the SSD for fast boot times and excellent system performance and then other applications and bulk storage will be stored on the HDD part. This is done by the user and its the user select which items they want on the faster SSD part of the drive. This type of setup is often referred to as dual drive hybrid system.
The true SSHD (Solid State Hybrid Drives) are SSD flash components built directly into the hard disk drive and as far as the system is concerned it is a single drive. This may seem like a worse solution for the user because they don’t get to choose what they get to store on the faster part of the SSHD, but this is where the software takes over. These drives are specifically setup to select the most used data (most frequently accessed data) Allowing for the best use of the SSD component of the drive. This is likely to be operating system files anyway but could also be shared resources or daily applications such as internet browsers. This is the bonus its whatever you use the most. This is called self optimizing mode.
There is a second mode for SSHD’s and that is host operating mode, in this mode the same optimizing effects can be had but the decisions of what files are stored on the SSD components are not made by the drive but by the operating system and device drivers or host software.
Comparing SSHD to HDD’s and SSD’s in benchmarking tests shows no surprise that the SSD’s are the fastest in all categories, but SSHD’s while not gaining any real speed advantage over Hard Disk Drives when it comes to read and write tasks, they do perform much better when it comes to loading and shutting down applications including the operating system, that means reduced boot times.
What’s the difference between a SSHD and a HDD with cache memory
Apart from the sheer size difference SSHD’s have GB’s of storage space and cache memory on hard drives is about 64MB on large drives the real difference is what they are used for. SSHD’s have a flash memory component for storing data, it is fast access for the computer to pull the data it needs from storage. The Cache on a Hard Disk is used as temporary storage for data that the CPU is currently working on so it has a faster access to the data it needs. The cache memory will not store applications or documents it will be raw data for processing. This is done to stop the CPU from having to wait for the slow hard drive to deliver the data it needs. Hard drives cache does not keep the data once it has been switched off, but the SSD component of the SSHD will hold all the data that has been put on it after the computer has powered down.
SSHD’s in laptop computers
Laptop computers are where the Solid State Hybrid Drives really come into their own. The fact that consumers and manufacturers want their laptop PC’s to be light and thin means that the fewer components inside the laptop the better. So if you need the performance boost of having an SSD inside your laptop but still need the cheaper bulky storage space of a hard drive then the SSHD makes perfect sense, both devices inside a single casing. Unlike desktop PC’s, laptop users tend to put their device into sleep mode quite a lot, whether that’s to move rooms or when they are on a train to and from work, the lid gets closed and the system goes to sleep. With the SSHD inside the laptop the data stored when the system goes to sleep mode is stored into the faster SSD component, allowing for a significantly faster wake up time over the traditional hard drive systems. Currently testing this on my Lenovo flex laptop with an 8GB SSD flash storage on a 500GB hard drive and the results are impressive. Going into sleep mode is basically instantaneous, and coming out of sleep mode is nearly as quick taking a fraction of a second from pressing the space bar to bring the system out of sleep to being able to type in my windows password for access to the system again. This is with applications running when the system goes to sleep as well.