Sata 6 Mysteries


Sata 6 Mysteries

Ask the Doctor LogoAre 6Gb/s SATA ports on the newer motherboards backward compatible like USB 3.0 is with USB 2.0? I’m eventually going to purchase either an Asus Crosshair 4 Formula or a MSI 890FXA-GD70 motherboard.

I need to know if my two Seagate Barracuda 7200.12 1TB hard drives will work in these motherboards’ 6Gb/s SATA ports. I won’t be using any RAID configurations. The first drive is for Windows 7 64-bit and programs. The second is going to be for the Documents, Downloads, Music, Photos, and Videos folders.

Also, when are 6Gb/s SATA hard drives for desktop computers going to be available?

—Keith Brooks

Yes, 6Gb/s SATA ports are backward compatible; you can run 3Gb/s SATA drives just fine on them. There are several 6Gb/s SATA drives on the market, including the 1TB WD Caviar Black WD1002FAEX, Seagate Barracuda XT 2TB, and the latest 600GB and 450GB WD VelociRaptors. Crucial’s 256GB C300 SSD runs on 6Gb/s SATA, as well. Aside from burst speeds and some alleged NCQ benefits, there’s not much to gain from running mechanical hard drives on SATA 6Gb/s. Some solid state drives, on the other hand, benefit immensely—3Gb/s SATA tops out at about 240MB/s, while the Crucial C300’s average read speeds on 6Gb/s topped 300MB/s. Not shabby!


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Marketing is pretty much lying efficiently. Which means take some facts and liberally sprinkle it with shiny sparkly lies. It is not true that if they didnt lie they would not sell anything. This is the way the cookie crumbles in the corporate world... Make some money tell some lies. Make more money tell more lies until you accumulate so much cash that you can defend your lies in a court of law if necessary. At that point the magnitude of your "marketing" does not matter because you can "defend" your marketing.  Most people want to be lied to because they are too lazy to read and research for themselves. Throw the industry cheerleaders into the mix (ie magazines) and you got a nice environment ripe for fooling those lazies. It is the same human pscyhe that somehow makes us belive that  59.99 is not 60.00 but it is much more like 50.00. Do you see where I am going with this here? We like to belive that we made the best choice by buying the biggest baddest number. So we as consumers have a fault in this because we just gobble it up.

Disclosing the entire truth would maybe hinder sales. A good example would be the trim function. Would people be more hesitant to buy SSDs if manufacturers claimed on the box that said " the more you use the slower it gets and we cannot guarantee a piece of software to remedy this. But maybe in the future." Trim help was not available for a long time.

However, I would like to add that not everyhing is a lie. A typical SSD performance is usage type dependent. I also would like to add that HD has been the single biggest bottle neck for decades. The good news is that with the advent of SSDs, hd bottle neck issue is poised to disappear.

You can achieve amazing speeds with SSDs by using Raid. Since sata ports provide dedicated independent channels, you can literally double the performance. Smaller SSDs are getting really cheap and those are excellent for raiding for a nice lightning of a boot drive. At the expense of an extra sata port there it is.. Your very own faster than sata6 solution.


In my case these are the benchmark numbers I am working with.

SSD setup consists of 2x 80 gig Intel Gen2 Sata3 units in Raid0 as boot drive.

CrystalDiskMark 3.0 x64 (C) 2007-2010 hiyohiyo
                           Crystal Dew World :
* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

           Sequential Read :   518.669 MB/s
          Sequential Write :   171.504 MB/s
         Random Read 512KB :   325.126 MB/s
        Random Write 512KB :   172.498 MB/s
    Random Read 4KB (QD=1) :    21.736 MB/s [  5306.7 IOPS]
   Random Write 4KB (QD=1) :    59.172 MB/s [ 14446.3 IOPS]
   Random Read 4KB (QD=32) :   277.514 MB/s [ 67752.5 IOPS]
  Random Write 4KB (QD=32) :   162.318 MB/s [ 39628.5 IOPS]

  Test : 1000 MB [F: 22.2% (33.1/149.0 GB)] (x5)
  Date : 2010/05/02 11:33:13
    OS : Windows 7 Ultimate Edition [6.1 Build 7600] (x64)


Bullwinkle J Moose

Question:  If 3Gbps Sata tops out around 240MB/sec, then why does OCZ and other Sata 2 SSD manufacturers provide read & write speeds over 270MB/sec in their specs?

Answer:   Because they couldn't sell any SSD's if they gave us real numbers!



We want REAL numbers!




You said that right Moose.

Theoretical speeds are usually bullshit. USB 2 or 3, firewire, IDE, SATA, ESATA even SCSI all fall short. Very short and will only approach those advertised speeds under ideal conditions which nomal users will never see.

Like you said, if they told you the actual speeds, they couldnt sell a single item.

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