Sata 3

rabb1t · 03-09-2009, 07:38 PM

Tom's hardware - Seagate, AMD Show Blazing Fast SATA 3

Quote:

... According to the demo, the SATA2 drive (a 7200.12 Barracuda) topped out around 288 MB/sec, running just below the standards top theoretical speed. The SATA 3 drive, a Seagate Barracuda SATA 3 prototype, reached a staggering 589 MB/sec, more than double the speed of the SATA 2 setup. ...
... In the case of SATA 3, the new drives will be 100 percent backwards compatible with SATA 1 and 2 ...
... According to the SATA-io website, SATA 3 (or SATA Revision 3.0) will be available in the first half of this year. ...

Woah.

Fozzik · 03-10-2009, 06:49 AM

That article doesn't make a lot of sense... except that the author is just quoting what he saw in some cheesy demo (the speedometers which are connected to who knows what, I suppose). There aren't any SATA 3Gb/s 7200 RPM drives that even come close to saturating the bus. They typically have sustained throughput around 100 MB/s and bursts around 150 MB/s, don't they? That's only using half of what is available right now...so why would we need to double the bandwidth?

Am I missing something here?

Just making the bus even wider wouldn't change the speed of the drive at all. If it's still rotating at the same speed, still using the same cache technology and everything else, it's not going to go any faster just because you plug it into a faster bus. If you have a pump that pushes a gallon of water a minute, you can connect it to a five inch pipe or a 20 inch pipe... it's still going to pump a gallon a minute.

This sort of thing always frustrates me. It will probably sell a lot of drives once they stamp the SATA 6 GB/s tag on the box...but it really doesn't improve the performance at all.

I suppose it will end up being useful for SSDs once they get a bit faster... they can probably actually use the extra bandwidth, as opposed to 7200 RPM mechanical drives which haven't gotten a whole lot faster in like 10 years.

Fozzik · 03-10-2009, 07:00 AM

Also, it bugs the heck out of me that most tech journalists are still making the mistake that they've been making for the last several years. The current SATA standard is NOT called SATA2, and It's very possible that they new standard is not actually called SATA3. The current standard is called SATA 3.0 Gb/s. It looks like the new one is called SATA 6.0 Gb/s.

If I'm not mistaken, SATA 2 was the name of the committee that came up with the updated standard, and a lot of people just started calling the drives and controllers SATA 2 on their own. Now it looks like the same thing is happening again. Unless maybe the committee has given up and decided to label the drives SATA 3 since that's what everyone seems to want to call them regardless of the actual name of the standard.

rabb1t · 03-10-2009, 01:30 PM

Quote:

Originally Posted by Fozzik

If I'm not mistaken, SATA 2 was the name of the committee that came up with the updated standard

The first one burned down? The second one burned down and then sank into the swamp?

Fozzik · 03-10-2009, 02:32 PM

Princess Bride?

Sounds familiar, but I can't remember.

rabb1t · 03-10-2009, 03:55 PM

Holy Grail.

The third one burnt down, fell over, then sank into the swamp. But the fourth one stayed up, and that's what yer gonna get lad.

Fozzik · 03-11-2009, 11:37 AM

Ah yes, well I'll tell you...

*he's going to tell, he's going to tell, he's going to tell....

EQ Companion · 03-11-2009, 01:52 PM

There is a new article on Anadtech about SATA 6Gbps and it revealed the transfer rates in the OP link were actually from the hard drive's 32MB read buffer!

Anyway, the article said that SATA 6Gbps will primarily be for future SSD's.

Here's the link:

http://www.anandtech.com/weblog/showpost.aspx?i=580

Tomcrit · 03-11-2009, 04:09 PM

I am with the Foz on this one it is all just marketing, people have been conditioned to see the bigger numbers and just assume they are better. As he mentioned the "sata2" drives don't come anywhere close to filling the bus in the real world. I ran some test over a period on mine when i installed them and they averaged less than 90MB/s. They are not raptors so there is some increase to be made (for a price) but raptors in real world use won't get an average to stretch the bus.

I recently built myself a Freenas server which has 2 1TB WD greens in it which are 3 GB sata drives but the old motherboard only supports 1.5gb sata and guess what they are roughly the same speed as my main machine with the 3.0gb sata onboard. I haven't done a sustained accurate test but the read/write speeds reported by various apps are pretty much identical.