SATA3 vs SATA2 RAID 0

[TimCDN]

Hi all,

Looking to build up my first Hack Pro with the new Gigabyte Z77X-UP5-TH.

Quick question:

I will be running a SSD off of one of the SATA3 ports as my boot drive. Which would be faster; using one Seagate Barracuda off of the other SATA3 or RAID 0 two of the same drives off of the SATA2 ports.

I think that the SATA2 RAID 0 would be faster, but I want to hear from the pros!

Thanks

 

[tot31]

Either will be the same.

 

[Albertsw]

Mechanical hard drives don't benefit from SATA 3. Only SSDs benefit from it.

 

[thelostswede]

Mechanical hard drives don't benefit from SATA 3. Only SSDs benefit from it.

Not true, but clearly the benefit is limited compared to an SSD.
You'd see more benefit in a RAID array.
However, in this specific case, you wouldn't see any benefit as you're using two difference bus speeds and the slower speed would be the one both drives would adhere to.

 

[TimCDN]

Thanks guys.

 

[pragsdale]

I am not sure that the last response (thelostswede) answered your question ...

My interpretation of your question is as follows (both options also include a SSD on a SATA3 port):

Option 1 - single Seagate Barracuda drive on a SATA 3 port

vs.

Option 2 - 2 x Seagate Barracuda drives in a Raid 0 configuration with BOTH drives on SATA 2 ports.

I believe that Option 2 would be the faster configuration for HDD ... this is what I am considering doing on the same motherboard for mass data storage (just ordered today).

 

[tot31]

Ok here is my AJA System Test score on 2 x 1TB HDD in RAID0 SATA 2 (both ports connected to SATA2)

Here is AJA System Test on 2 x Intel 330 60GB SSD in RAID0 with SATA 2 & SATA3 (one port connected to SATA2 and the other to SATA3)

Here is AJA System Test on 2 x Intel 330 60GB SSD in RAID0 with SATA 2 (both ports connected to SATA2)

 

[ggeorge]

Not true, but clearly the benefit is limited compared to an SSD.
You'd see more benefit in a RAID array.
However, in this specific case, you wouldn't see any benefit as you're using two difference bus speeds and the slower speed would be the one both drives would adhere to.

When would you see a difference with mechanical drives? AFAIK, not even the new 1tb Raptor will exceed 300 Mb/sec.

 

[thelostswede]

When would you see a difference with mechanical drives? AFAIK, not even the new 1tb Raptor will exceed 300 Mb/sec.

True, but have you compared a SATA 3Gbps to a SATA 6Gbps drive? Some of the newer SATA 6Gbps drives can hit close or even over 200MB/s, so a couple of those in RAID will take advantage of the SATA 6Gbps interface.

SATA 6Gbps also added better NCQ support and various other features that SATA 3Gbps doesn't support, something SATA 6Gbps drives can take advantage of.

 

[ggeorge]

True, but have you compared a SATA 3Gbps to a SATA 6Gbps drive? Some of the newer SATA 6Gbps drives can hit close or even over 200MB/s, so a couple of those in RAID will take advantage of the SATA 6Gbps interface.

I'm confused, how does RAID enter into this?

Unless my understanding of things is vastly mistaken, the bandwidth on a sata port is per port. So two 200 GB/s drives on two separate 300 GB/s ports would be (I know it's not this simple) 400 GB/s. So I'm not seeing how the SATA 6Gbps is going to make a difference. The 6Gbps only helps if you are exceeding the throughput of the 3Gbps port, which the mechanical HDDs just can't do currently.

Are you thinking of something like Port multipliers that let you hang more than one device like a RAID box off of a port? Or something like with SAS drives? I think that can support more than one drive per port as well.

SATA 6Gbps also added better NCQ support and various other features that SATA 3Gbps doesn't support, something SATA 6Gbps drives can take advantage of.

The NCQ support improvements would seem to be marginal at best. I mean just about any SSD completely destroys a mechanical drive when it comes to things like random access and IOPs. I've got an 8 disk Raptor 150 RAID-5 on an Areca-1230 wt 1gb cache and it only hits about the performance level of my Samsung 830. Granted both the disks and the RAID card aren't exactly state of the art, but it takes a HELL of an expense to get close to the performance of just one or two SSDs with mechanical HDDs. That was about $3500 worth of hardware back when it was purchased (granted it WAS about 6-7 yrs ago).