Excessively numpty question about SSD

[mickledore]

I'm looking to update my laptop, but know nothing about tech specs. I've been given the run around by one firm who would build something for me, but I've no idea what they were offering, so they had the order of the boot.

My question...what's the difference between SSD and a hard disc? I know it's stupid but I don't know the difference. I was offered this spec:-
1TB SERIAL ATA II 2.5" HARD DRIVE WITH 8MB CACHE (5,400rpm)
SSD CACHE DRIVE
120GB Kingston SSDNow mS200 mSATA (upto 550MB/sR | 520MB/sW)
What does this all mean? I presume there are two drives - yes? At present my laptop has a hard drive where programmes, storage and everything else works from (I assume).

If there are two drives what does each do, , and if SSD is so good why not just have the one? Are programmes on one and storage on the other, or is there some other benefit?

Can anyone enlighten me, without using too many techy words that I don't understand?

 

[TCR4x4]

SSD's are far faster to read and write information than standard hard disks, meaning things load and save much faster.

In the spec you have listed, the SSD would be best holding all the programs and operating system, and the other will hold all the documents.

Currently people have both, as SSD storage is still very expensive. You can buy 500GB+ SSD's, but they are eyewateringly expensive, so we must make do with traditional drives to hold our everyday data.

Im sure in 5 years, HDD's will be a thing of the past and SSD's will do everything.

 

[ancient_mariner]

An SSD cache drive combines SSD and conventional HDD technology, with a degree of cost benefit. The drive store regularly accessed data - like operating system and program files - on the SSD section for rapid transfer, while less frequently used data is stored on the conventional spinning rust of the HDD. In use this hybrid drive 'learns' what files are used most frequently and stores transfers them to the SSD section. In practice they are a compromise, as I understand it, and can be faster than a conventional drive, but not as fast as an SSD, especially for data that is stored on the conventional drive. You'll see faster boot times and programs will open quicker, but they'll be just as slow when opening images.

There's another thing too - SSDs work better when the drive is not cluttered. You can fill a conventional HDD pretty much to the brim, but SSDs slow down as they fill.

120GB Kingston SSDNow mS200 mSATA

Kingston is the make, SSDNow mS200 the model and mSATA the type of connector to join the drive to the motherboard of the laptop (mSATA = micro serial ATA).

I have a 128Gb Samsung unit in my Macbook, and try to ensure I have 50Gb free most of the time. If I were buying a new machine then I'd want either a 256Gb SSD as the sole drive, or a 128Gb + 1TB HDD if the machine could manage dual drives.

 

[arad85]

The primary difference between SSD (solid state drive) and HDD (hard disk drive) is that an HDD is a mechanical device. The fact it is mechanical implies that certain things take a lot more time to do on them. When you ask to read some data, an SSD sets the address lines and reads data. The data is then given back to you - PDQ. When you ask for data on an HDD, the device has to calculate where that data is, position the read head to the right distance from the centre, wait for the disk to spin to the right point and then read the data. This (in computer terms) takes an age. Having said that, byte for byte, HDDs are WAY cheaper than SSDs, so it is a balancing act.

It sounds like you are being offered a system with 3 disks in. 1) The 120GByte SSD which will likely be used for the OS, 2) The 1TB HDD, 3) A small (around 20GB) SSD which the system will use as a cache drive for the 1TB HDD. The 1TB/Cache drive becomes a hybrid SSD/HDD and has some of the benefits of both - it is still relatively cheap but also has fast read/write performance for some of the data. Which data gets stored in the cache drive is dependent on the system and you don't really control that. As far as you as the user are concerned, you see 2 drives - the SSD and the hybrid drive.