SATA speed?

[phiii]

Hey there.

What do you think of the following?
I put in a Samsung Spinpoint F3 HD502HJ, officially SATA 3Gbps.
using an Asus P8H61-I with 4xSATA 3Gbps ports.
put in the usual red SATA cable (which should support 3Gbps?) and get reading top speeds of ~150MB/s. although 3Gbps should mean ~300MB/s.
I also have a black SATA cable at home which is designated for 6Gbps, do you think it is worthwile to change the cable?
Because my case is quite small it was a huge effort to cram everything into it and I would rather like to not open this pandora box again...

thanks for your opinion,
phil.

 

[Durntdude]

Technically 3 Gbps means a theoretical max if 375 MB/s which (if saturated) would likely be closer to 300-320, maybe 350.

However, that is the interfaces max speed of transfer, not the actual hard drives transfer. 7200 rpm hard drives realistically will never exceed 130MB/s. Heck, most don't get over 100MB/s.

It's basically saying that you could support up to 375 MB/s if only the hard drive could provide it

EDIT: According to wikipedia, max hard drive to buffer speed on 7200 rpm drives is 1030 Mbits/sec or 128.75 MB/s

 

[Forceman]

Technically 3 Gbps means a theoretical max if 375 MB/s which (if saturated) would likely be closer to 300-320, maybe 350.

However, that is the interfaces max speed of transfer, not the actual hard drives transfer. 7200 rpm hard drives realistically will never exceed 130MB/s. Heck, most don't get over 100MB/s.

It's basically saying that you could support up to 375 MB/s if only the hard drive could provide it

EDIT: According to wikipedia, max hard drive to buffer speed on 7200 rpm drives is 1030 Mbits/sec or 128.75 MB/s

Pretty sure there are 7200rpm drives now that can do 140 MB/s because of the increased densities from 1TB platters. That being said, no spinning disk is going to exceed SATA 3Gb speeds, but SSDs can and do.

 

[Durntdude]

That might be right. I was basing my previous post on past knowledge and a little Wikipedia >.>. Must of missed a few tech articles.

 

[phiii]

Okay, thanks for the answers.
Good to know that I don't have to change the cabling.
The guy who sold me the 6Gbps SATA cable said it would remove a bottleneck as data transfer from disk is limited by the cable... very competent in hindsight
Cheers,
phil

 

[dustNbone]

There is no such thing as a SATA 6Gbps cable. The cable spec hasn't changed since SATA 1.5Gbps.

 

[drescherjm]

Pretty sure there are 7200rpm drives now that can do 140 MB/s because of the increased densities from 1TB platters. That being said, no spinning disk is going to exceed SATA 3Gb speeds, but SSDs can and do.

Yes. 7200 RPM drives with 666 GB or greater platters can and do go over SATA I speed of 150MB /s.

 

[drescherjm]

There is no such thing as a SATA 6Gbps cable. The cable spec hasn't changed since SATA 1.5Gbps.

Agreed. SATA 6Gbps cables are a marketing gimmick. The standard has not changed from the original spec for SATA I cables to SATA III cables.

 

[drescherjm]

Technically 3 Gbps means a theoretical max if 375 MB/s which (if saturated) would
likely be closer to 300-320, maybe 350.

I believe SATA uses 8/10 encoding like SAS meaning the limit is 300 MB/s for SATA II. Although I may be wrong on that one.

 

[daglesj]

The only positive changes I've seen to SATA cables are the clips they should have had from day one.

 

[Old Hippie]

The guy who sold me the 6Gbps SATA cable said it would remove a bottleneck as data transfer from disk is limited by the cable... very competent in hindsight

LOL!

Don't feel to ashamed. I've seen people on this board actually argue about the difference,,,,,but there isn't any.