Sata 2 vs Sata 3 HDD

[Tekified]

Hi guys quick question about my sata 2 and sata 3 drives using ATTO.

Sata 2 Samsung DH103SJ 1TB 32MB Cache

Sata 3 Western Digital WD1002FAEX 64MB Cashe

The Samsung Sata 2 HDD gets close to 140MB Read/Write past 8k

The Western Digital Sata 3 HDD gets about 125MB Read and 123MB write pask 8k


Confused as to why my sata 2 appears to be faster than my sata 3 HDD?

I trust ATTO's results.


I thought sata 3 would be much faster but looking at ATTO benchmarks online
for the Western Digital Sata 3 HDD 120MB read/write is what others get also.

Any ideas?

 

[Murissokah]

I think your SATA II drive IS faster. The bandwidth provided by the SATA 2 interface is more than enough for any HDD. The drive itself is faster than the WD, thus better speeds. There is no gain in R/W speeds for HDD in SATA 3.

 

[Tekified]

Thanks for the reply! My next question is...Why do they make SATA 3 drives if my SATA 2 drive is just as fast if not faster? Cheers

 

[RetiredChief]

^ Correct. A mechanical HDD is limited in its throughput by Platter density and RPMs which prevent it from exceeding Sata II bandwith. Performance then becomes related to the Drive and NOT the port.

The Only performance gain for a sata III drive on a SATA III interface is burst rate, and that is limited in overall performance as it only benifits the first second or two of read/writes.

Why sata III HDDs - what manufactor wants to advertize a drive with Yesterdays technology - LOL

 

[ukee1593]

the Samsung Spinpoint F3 drive is one of the fastest 1TB drives on the market ... so no doubt it will beat a WD 1TB SATA 3 or not!!

As Murissokah said ... SATA 2 has more than enough bandwidth for ANY mechanical HDD (Heck SATA 1 would rarely slow a HDD down either), so you simply aren't getting any speed gains from SATA 3.

The only way that the SATA 3 will help on the WD is with access to the drive cache. This is only 64 MB ... so not very noticeable in the end!

 

[Murissokah]

SATA 3 is necessary for high-bandwidth devices, such as SSDs.

SATA 2 = 3 Gbit/s, max 300MB/s.
SATA 3 = 6 Gbit/s, max 600MB/s.

Some solid state drives reach over 500MB/s.

 

[quilciri]

Thanks for the reply! My next question is...Why do they make SATA 3 drives if my SATA 2 drive is just as fast if not faster? Cheers

To take advantage of people who don't know any better. There's no real point to a SATA 3 interface on a HDD.

 

[Tekified]

SATA 3 is necessary for high-bandwidth devices, such as SSDs.

SATA 2 = 3 Gbit/s, max 300MB/s.
SATA 3 = 6 Gbit/s, max 600MB/s.

Some solid state drives reach over 500MB/s.

I am using a Crucial M4 128GB SSD for my boot drive...maybe it's better to keep my SATA 3 instead of the SATA 2 HDD

 

[Murissokah]

SATA 2 and SATA 3 channels are isolated from each other. It won't matter what other drives you are using, as long as the SSD is connected to a SATA 3 port. Also, if your motherboard has more than one SATA contoller 3, be sure to use the fastest one (usually Intel). Check for that on the motherboard documentation, or just tell us what mobo you have.

Samsung spinpoint drives are really good. I use a pair of them, they're fast and reliable. Are you going to remove one of the HDDs? I think you'd do well with either one.

 

[Tekified]

SATA 2 and SATA 3 channels are isolated from each other. It won't matter what other drives you are using, as long as the SSD is connected to a SATA 3 port. Also, if your motherboard has more than one SATA contoller 3, be sure to use the fastest one (usually Intel). Check for that on the motherboard documentation, or just tell us what mobo you have.

Samsung spinpoint drives are really good. I use a pair of them, they're fast and reliable. Are you going to remove one of the HDDs? I think you'd do well with either one.

If you had to choose which one to keep and which to sell what would you do? I can only choose one, cheers

 

[Tekified]

I have the Gigabyte GA-Z68AP-D3

 

[Murissokah]

Performance is similar, I would keep the newest one, or the one with longer warranty.

Your motherboard has only one SATA contoller, the one from Intel, so you are fine with whatever SATA 3 port you use for the SSD. The HDD may be connected to any SATA port.

 

[Tekified]

I've ordered a Kingston HyperX USB 3.0 flash drive which has the following speed

225 MB/s (read) 135 MB/s (write)

This seems faster than SATA 2 or 3 so for a backup drive shall i buy a USB 3.0 Hard drive? I know it's more expensive but much it's faster isn't it?

Cheers

 

[Tekified]

Just to update you all. I plugged the SATA 2 drive into the SATA 3 port and the speeds are a consistant 140MB/s

I will use this now instead of the Sata 3 Western Digital WD1002FAEX 64MB Drive.


Many thanks!

 

[motilv]

SATA 3 HDD is slower than ssd. If you want your ssd to better performace, you can add an pci-e to sata iii card to your motherboard.