SATA III SSD on SATA II controller

[JJ Johnson]

Will a SATA III SSD attached to a SATA II controller be bottlenecked by the connection? Specifically, I was considering installing a 64GB Samsung 830 to upgrade the system disk on my home server, which has only SATA II headers on the motherboard.

 

[jwcalla]

For some operations -- like sequential reads and writes -- your speeds will max out at SATA II speeds.

The disk can not operate any faster than the controller.

However for a lot of the important day-to-day operations where access time and random read / writes are common, the speed difference is not as dramatic and mostly imperceptible.

 

[brutalizer]

Yes, it will. I am using a Vertex 3 in a SATA 2 connection. But still, the SSD is way faster than a hard disk, so I use it to great satisfaction. I suspect that IRL it will be hard to tell the difference. Usage responsivity is a complex thing

 

[JRS]

For what its worth, I was running my Samsung 830 on a P5Q Deluxe (sata II of course) as the boot drive for a few months before I built my 3570k machine.

Booting seems a second or two faster with the 830 on Sata III vs II. Obviously not a fair comparison as I'm comparing completely different systems. I've not tried booting the 820 off a Sata II port on my z77 motherboard.

I would describe going from booting with the 830 on a Sata III port vs a Sata II as only 1/10 as big of an improvement as going from RAID0 10K mechanical boot to Sata II SSD boot.

Deleting a virtual machine snapshot on stripped velociraptors, ~10-20 secs, on 830 on Sata II port ~5 secs, on 830 on Sata III port, almost instant.

Moving big files, virtual machine images for example, between the 830 on Sata III to/from the striped velociraptors is the most noticeable improvement vs. the 830 on Sata II to/from the striped velociraptors. This is a bit odd as you'd think the velociraptors would be the bottleneck in both cases and the interface the 820 was on would not matter. Go figure.

Those two scenarios is where I've noticed the Sata III performance the most. Almost anything else I do, no real difference.

Don't sweat not being able to put your SSD on a Sata III port. You will still get a huge benefit in performance.

 

[plagas]

I run a Crucial m4 on a sata 2 controller. I get like 270mb reads. It's freaking awesome.