SSD vs. SATA 3.0

SATA is Serial ATA - the cable where all the data goes through. It comes in three flavours:

SATA1 or SATA/150 = 1,5Gbps or 150MB/s
SATA2 or SATA/300 = 3,0Gbps or 300MB/s
SATA3 or SATA/600 = 6,0Gbps or 600MB/s

But even if the cable is capable of 600MB/s, it does not mean you get 600MB/s transfer speeds. Most HDDs are still limited to under 150MB/s to no HDD would have a significant benefit beyond SATA/150.

It's like driving on a highway with a maximum speed limit of 600 km/h but your large truck can only do 100 km/h and only when it doesn't have to take any turns. An SSD can go up to 350 km/h and can take turns very quickly.

The real difference between HDD and SSD is access times and IOps; which are hundreds of times better than HDDs. Copying large files is less suitable to SSDs; they are only twice as fast as HDDs in this area.

Hi Messa, I know this is an old thread, but my question is pretty similar.

Are you saying that if I owned a 10k SATA3 HDD, with a SATA3 motherboard (SR-2) and a SATA3 cable (lol) that it will still be limited to 150MB's? If not, how will it compare to SSD?

Thanks!

^SATA cables are SATA cables, the transfer rate and performance is determinate by the interface.

godbrother, you understand correctly. Although the SATA3 (more correctly, the SATA 6.0 Gb/s) interface has a MAXIMUM BURST RATE for data transmission of 6.0 Gb/s, the limit for ALL SATA 6.0 Gb/s devices is within the device itself. There are NO hard drives (that is, the "mechanical" ones with turning disks on a spindle and moving heads on an arm) that can move their components fast enough to deliver AVERAGE performance of better than 1.5 Gb/s. Most are slower than that, but a few with very fast revolution rates (10K and 15K rpm) can reach or slightly exceed that speed. ON the other hand, current SSD's with no moving parts regularly achieve twice that AVERAGE data delivery performance, but still not up to the full capacity of the SATA 6.0 Gb/s interface. In future we all hope that SSD's will get even faster, bigger and cheaper. But the design of the SATA 6.0 Gb/s interface was deliberately MUCH faster than any anticipated device, so the interface itself would not be a limiting factor.

Question: Since SSDs connect to the motherboard using the SATA cables, it would be best to get a SATA 3 mobo if I am buying now? Even though the current SSDs don't reach the 6.0 Gb/s it could cross the 3.0Gb/s soon and then the bottle neck would be the SATA II connectors?

SATA 3 is becoming more common. If I was buying one, and the difference between a SATA 2 MB and a SATA 3 one was 5 or 10 bucks, I'd do it.

One thing I've learned is, don't freak out about what might be in 5 years. Get something that is good for you for today or a few years. In 3-4 years maybe SATA 4 and the Intel 7500000 processor rule the world, and your 4 year old SATA 3 capable MB would be an antique.

Found my way to this thread on a quest to build my first system.

Buying sometime this week the ASUS M4A88TD-V. It's about $20 more than lesser boards by ASUS in the same theme that are USB2 and SATA2. It also got me the 128mb sideport memory so I don't need to buy a video card, but I'm not a gamer.

Also: most HDDs I've looked at are available in SATA2 or SATA3 for about the same price.

Some food for thought:
I have an idea of a crazy fast boot drive, but I only started learning about hardware a month ago. CompactFlash cards are IDE native. Grab a couple adapters and some fancy UDMA6 600x cards and you could smoke a consumer grade SSD. But that's way to expensive. The new CFast cards are native SATA and cost hundreds a gig for industrial applications (check out the brand addonics).

Realistically ($100), you could get 4x4GB CF cards UDMA4 250x and 4 adapters for about the same price/speed as a 16GB SSD. RAID 5 for security at the cost of capacity, or RAID 0 for kamakazi style. The 2 drawbacks are that it CF has a limited lifespan based on writes and that it is a silly idea anyway.

I can't help but remember the time my dad spent $160 on vacation for a 1GB SD card and I got one for $30 6 months later. My main problem with buying an SSD at this time is that too much of the price is just for the newness of the idea.

SSD is the future. Mechanical drives have mechanical limitations. Ask your mom or kid sister what an SSD is. The day they can answer that, they will become affordable. I'm probably going to RAID up some Caviar blacks or Samsung F3's and wait for the prices to drop.