SATA-II explained

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This is a great thread... Will be building a C2D system soon and was going to get a new SATA-II HD, but seems as i won't be using RAID, it looks like there'll be no speed benefit over SATA-I, so i can still keep my old SATA-I, and spend the savings elsewhere... :D
 
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Hello,

I'm wondering why this guide seems to be both technically incorrect and why it contradicts itself. Allow me to explain.

The first sentence says:

SATA-II was the name of the organisation setup to write the specifications of the Serial ATA 2.5 generation drives and possibly beyond. However, since the confusion caused by manufacturers of drives naming drives SATA-II, they have changed their name to SATA-IO (Serial ATA International Organisation).

In this, you clearly state that SATA-II is the former name of the SATA organisation and not a drive standard, then the rest of the guide goes on to talk about SATA-II drives. The image at the bottom of the guide also makes no mention of SATA-II other than to say "Don't use it". And there's the first part of the guide which tells you about what doesn't constitute a SATA-II had drive, but nothing about what actually does constitute one.

SATA-IO's own website states:

The term SATA II has grown in popularity as the moniker for the SATA 3Gb/s data transfer rate, causing great confusion with customers because, quite simply, it’s a misnomer.

The first step toward a better understanding of SATA is to know that SATA II is not the brand name for SATA’s 3Gb/s data transfer rate, but the name of the organization formed to author the SATA specifications. The group has since changed names, to the Serial ATA International Organization, or SATA-IO.

Again this clearly states that SATA-II is not a specification or a brand name, but the former name of the SATA organisation.

These days, many manufacturers are now using correct terminology. For example, visit Seagate's website and you won't see a single mention of "SATA2" or "SATA-II" anywhere on the site. The same goes for Western Digital's site. Again, not a single mention of this illusionary "SATA-II" standard anywhere. Or there's Intel's site. Trawl all around the details of their chipsets and yet again, no SATA-II anywhere in sight. You'd think that if such a standard did actually exist, the manufacturers would use it when explaining the features of their products. The fact that they don't quite clearly enforces the fact that there isn't actually such a thing as a SATA-II hard drive in the first place.

Other suppliers such as Dabs have also completely dropped the flawed idea about SATA-II/SATA2 and simply mention the supported bus speed of the drives along with any other supported SATA features.

And so the question begs, why does Overclockers continue to talk about products which are based on a none-existant standard? It actually puts me off buying future products from them when I see all of these wonderous SATA-II drives mentioned, despite the fact that this FAQ even admits initially that it's not the name of a standard and is unable to actually clarify the requirements which constitute such a drive. Obviously if you are to buy products from a supplier, you'd expect that supplier to be capable of properly describing the products that they're selling.

If someone could please explain why Overclockers still market drives etc. in this way, I'd love to hear why. Oh, and also as a side note, I'd be interested to know why Overclockers are also advertising "SATA-2 cables" on the site as well, despite stating in this very FAQ that all SATA drives use the same type of cable.

Many thanks,

Dave.
 
Soldato
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Thanks Dave, but if you ready my sticky, you'll notice I use quotation marks for 'SATA-II' as, whilst you might be well aversed with Serial-ATA Generation 2 specifications, to give it its proper name, the average consumer is not. I created this sticky to help people understand the fallacy that exists amongst many consumers, most notably when we started to see 300MB/s drives appear. You'll also notice that I provide a table which is from the SATA-IO website clearly showing what constitutes what a Generation 2 drive is, which is not very much at all - the SATA-IO specifications are indeed the Serial-ATA Generation 2 specifications.

Rather than simply picking apart a fellow users post, albeit not particularly well, why not spend your time trying to improve it and making suggestions to me on how I can do this. I am not affiliated with OcUK, I'm simply trying to help out fellow community people. I have taken much time to ensure all data is accurate and intelligible for all. If you find this difficult/contradictory etc in any way, please make suggestions on how I can best improve it. You'll not know, not being around the forums for very long, that most of the questions I list are exactly the types of posts I was answering on a daily basis. Rather than repeat myself, I made this thread to answer most of these questions which were are very frequently at the time.

Rather then spend my time firstly rubbishing the misnomer to which the average consumer is accustomed, I simply used it 'quoted' though, I now see that I did not use it uniformly, however this was my intention. I used the 'SATA-II' moniker to ensure that the consumer could easily understand all the relevant information. I thought it to be the best method of dealing with the issue. People would come into the thread thinking SATA-II = 300Mb/s, so I used the symbolism of what SATA-II encompassed to define generation 2 without the necessity for this guide to be overtly complicated. As I have said though, if you are unhappy, please feel free to write your own guide, and make a thread out of it. I have linked to sata-io website, in the first question, so all the relevant information is there.
 
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Associate
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Thanks for your reply and I apologise for initially assuming you were at all affiliated with OcUK. Sniping and simple nit-picking was not my intention and so I apologise if that's how it came across.

My irritation generally stems from posting on several other tech forums where we regularly get people coming along with specs of new parts that they're after which may include a hard drive from OcUK. Then the questions start such as if this SATA-II drive will work on their motherboard because the manual doesn't mention SATA-II, are special cables needed, is SATA-2 incompatible with SATA-1, will I have to throw away my existing SATA-1 hard drive and all the rest of it. As you state yourself, this whole SATA-II fiasco just causes huge confusion and a big set of questions to answer.

The result of this is me being repeatedly forced to point out that despite how OcUK advertises drives, SATA-II simply doesn't exist as a drive standard. SATA is SATA. There have been extensions to the standard such as the 300MB/s (or 3Gb/s however you look at it) interface speed, support for hot swapping, NCQ, etc. But at the end of it, it's just SATA with extensions to the original specification and not a brand new succeeding technology or anything.

Hence pretty much all SATA drives work with all controllers and all other SATA drives using any SATA cable. The only exception of course being the flaw on a few early 150MB SATA controllers which prevent them from using auto-speed negotiation to work with 300MB drives. A flaw which is worked around by jumpering the drive to force it to use the 150MB interface speed.

This is ultimately the kind of message which I believe should be pushed as it helps to quell so much of the confusion which has been caused by SATA-II. For example when UDMA100 came out to supersede UDMA66, there were no issues with drives being labled as "IDE-2" or anything, no major problems with people expecting controller/cable incompatibilities and virtually none of the sets of questions which I keep facing on other forums which are often being fueled by OcUK (and again, I realise that's nothing to do with you so don't take it as a personal snipe or anything). It's just that by acknowledging SATA-II and then mentioning SATA-II drives and what constitutes them, you just fuel the illusion that it's a new standard needing new controllers, cables, etc. You're then of course forced to begin pointing out how this isn't the case. Far better IMO to avoid that situation in the first place really.

Personally, I'd like to see the FAQ re-written to point out that SATA is SATA, extensions have been made to the spec and drives that sport these - particularly NCQ are handy over earlier generation SATA drives. But a SATA drive will work on pretty much any SATA controller using any SATA cable with the exception of the Auto-Speed Negotiation issue which I mentioned above. More info about guilty chipsets and how to jumper drives for 150MB with these chipsets could then be provided. Other details in your FAQ about Hitachi drives being jumpered for 150MB by default etc. are handy to keep along with any other such useful information.

Obviously this then generates the issue of a forum for a supplier telling people that the supplier is advertising products incorrectly, but well! That's up to OcUK to consider fixing.

Regards,

Dave.
 
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Soldato
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No problem Dave, that sounds like fair comment. Admittedly, the sticky is now 1.5 years old, and quite possibly could do with updating. I have noticed most resellers dropping the 'SATA-II' moniker for 300MBp/s drives. I only left the sticky as it was as OcUK have kept the naming scheme. Invariably, this led to lots of questions akin to the above being asked, which meant that I 'had' to answer them. I must have answered about 5-10 posts a day on this very issue and it was diluting the real questions being asked in this forum.

I shall think up an new way of describing the new specs, perhaps 'SATA specification generation 2' would be appropriate terminology as this is exactly what has happened. The problem with this also is that we will no doubt end up with 'SATA-II' or 'SATA2' again. It will be very hard to dispel the naming scheme, largely due to retailers from the outset.

The big problem here is that the new specifications are indeed like a new generation, however there is backwards compatibility. To list out all the offending chipsets would be very difficult given that there are so many still used on all types of boards dating back to the Athlon XP and P4 Northwood days.

It might be possible to name them 'Serial-ATA IO specifications', stating that IO is the acronym for International Organisation, and I can add a note to this effect at the very beginning.
 
Associate
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Something like that would be fine. Second generation SATA drives would be an appropriate way of describing them. But even then it's difficult as so many of the newer SATA features are optional anyway as you point out yourself in the current FAQ. Even the SATA-IO site is unable to clearly clarify what features later generation drives should have. In fact I think that their current recommended approach is to state simply the interface speed and features supported by the device rather than using any form of encompassing name for the features. If you like, this flexibility is part of the problem. the new generation stuff is indeed like a new specification, it's just that everything is optional and hence it's difficult to tie a new name to drives that support one or more of the newer features.

The FAQ would be handy I feel if it points out that SATA-II/SATA2 isn't a new version of SATA, but merely a (poorly conceived/confusing) way of describing SATA devices which support one or more features from the second generation specifications. And hence it's just "Better/Improved SATA" rather than "Oooh, completely new version of SATA".

I also accept your point about the age of the FAQ. A year or two ago almost everyone was going on about SATA-II (me too initially) before the SATA-IO changed their name and started complaining about how the term was being used.

As for issues with chipsets etc. I was more meaning this to be a "work in progress" part really. ie, someone finds a problem with a certain chipset, mentions it and it gets added rather than a definitive list or anything. Just a suggestion of course. If you feel it'd be easier just to say "certain older chipsets have problems unless a 300MB drive is jumpered to 150MB" rather than trying to list specific chipsets, that'd be fair enough as well.
 
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Going on some of the previous posts, here's how I'd re-write the FAQ. Feel free to use as much or as little etc. as possible. I've tried to keep the layout and important information from the original FAQ as much as possible.

------

Right, there have been many posts and threads recently asking about 'SATA-II' drives. This is a small explanation of these drives and what SATA-II really is.

SATA-II was the name of the organisation set up to write the specifications of the Serial ATA 2.5/2.6 generation drives and possibly beyond. It is not the name of a new drive standard. However, since the confusion caused by manufacturers of drives naming later drives SATA-II (a practice which is now dying off), they have changed their name to SATA-IO (Serial ATA International Organisation). It is important to note that SATA-II/SATA2 does not actually exist as a new drive standard and is merely a term sometimes used (erronously) to refer to drives which support some of the later SATA features.

Here is a small FAQ regarding SATA, SATA2, SATA-II, etc:

1. How many versions of SATA are there?

- There is currently only one version of the standard simply called 'SATA'. Extensions have been added to this in various generations of the specifications (currently up to generation 2.6) and these include support features such as the 3.0Gbit/s or 300MB/s (see point 4) interface speed, Native Command Queuing (NCQ), staggered spin up to name but a few. These extensions are optional and SATA drives can support as many or few of them as they like. Several suppliers still use the term SATA-II to refer to drives which support one or more of these extensions (particulaly the 3.0Gbit/s interface speed) - contrary to the wishes of the SATA International Organisation. Other companies (Seagate, Western Digital, etc) have now dropped the term.

For a table of the Serial ATA features, please see the table at the base of this mini-FAQ.

2. Is there a different power cable for 'SATA-II'/SATA300 drives or do I need an adapter?

- All SATA drives use the same type of power cable.

3. Is there a different data cable for 'SATA-II'/SATA300 drives?

- All SATA drives use the same type of data cable, regardless of whether they support the 3.0Gbit/s interface speed or not.

4. Why are some drives/controllers listed as SATA 300MB/s whereas others are listed as SATA 3.0Gbit/s? Which one is faster?

- Both are different terms used to refer to the same controller/drive speed. The 3.0Gbit/s rating means 3 Gigabits per second and is the raw speed with which the controller/drives operate at. Due to the 8b10b coding overhead which SATA uses, the actual uncoded transfer-rate is 2.4 Gbit/s which is the same as 300 Megabytes per second. Effectively though, both terms mean the same thing. The same applies to SATA150 compared with SATA 1.5Gbit/s.

5. Will my new 'SATA-II'/SATA300 drive work on my SATA150 controller (and vice versa)?

- All SATA drives should work with all controllers. This includes SATA300 drives working on SATA150 controllers and vice versa.

NOTE: Some SATA150 controllers do not support auto speed negotiation. When using a SATA300 drive with such a controller, it is necessary to change a jumper setting on the drive to force the drive to use the 150MB/s interface speed. The best approach is often to try the drive out and to change the jumper if the drive is not being detected in the BIOS when the system is powered up. Some owners of SATA300 drives may still experience problems however as some older SATA300 drives may require a firmware flash of their drive (in which case the manufacturer will need to be contacted). These issues arose as a result of manufacturer's bridging chip and firmware conflicts. Some drives have no jumpers e.g. Hitachi and require a firmware setting to be changed - see Q7 below. In most cases however, a SATA300 drive should function fine on a SATA150 controller.

6. Will I notice a big performance increase from a SATA300 drive over SATA150 drive with, for example the following extra features: 16MB cache and NCQ?

- No. The 3.0Gbit/s transfer rate would only come into play if you had a controller which supports the full 3.0Gbit/s transfer or a RAID array with probably at least 4 disks - a single 7200RPM drive will have a maximum external transfer rate of about 58MB/s (as opposed to the 300MB/s available). Thus, in single drive configurations, SATA300 drives show no increase over SATA150 or even IDE for that matter seeing as they will all have an external transfer rate of around 55-60MB/s (7200rpm drives only).The only performance increase you will see is through the 16MB cache (should help writing and reading performance) and NCQ (Native Command Queuing) so long as your motherbard supports it. Thus, the performance increase will not be great over SATA150 drives, if at all, depending on features of the specific drive.

7. Will my SATA300 drive work out of the box at the full interface speed of 3.0Gbit/s - I have a compatible motherboard?

- Yes, for the most part. Hitachi drives are slightly different. For compatibility reasons, Hitachi default their drives to 1.5Gbit/s. To enable the 3.0Gbit/s interface speed on Hitachi's, you must download their Feature Tool and enable it from within DOS.

8. Can I run a SATA300 drive with a SATA150 drive and still get the full rate on the SATA300 drive?

- Yes. They will be on separate channels and so long as your SATA controller supports 3.0Gbit/s transfer rate, then they will run as intended. The same applies to combining drives where only one drive supports features such as NCQ as well.

9. How can I tell if my SATA300 drive is running at its intended 3.0Gbit/s, I have full support for it?

- If you have an nForce 4 board with the nF4 SATA drivers installed, the easy way is to look in Device Manager. Look at the properties of the SATA controllers under IDE ATA/ATAPI controller and there is a tab in there which displays either SATA Generation 1-1.5G for SATA150 and SATA Generation 2-2.5 (iirc) for SATA300. Otherwise, please download HDTach. Perform a quick test on the relevant drive and look at the burst speed. SATA150 will max out before 150MB/s but SATA300 will surpass this up to 300MB/s.

The actual specifications for Serial ATA drives can be found in this table:

satanamingchart0vs.jpg


Notice how many features are actually optional. Thus, ensure you know the actual specifications of the drive before purchasing.
 
Soldato
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Duly noted.

Looks perfectly fine - do you think you can email me a copy of the actual text? i.e. click edit, cut and paste into notepad and email this to my trust email. It saves me having to fiddle about with a lot of code.

I'll add any amendments or addendums afterwards...

EDIT: I am an idiot - I can just use quote...
 
Caporegime
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nice guide. can someone just explain briefly (don't think i seen it up there) why my new 400GB Samsung sata II 16mb has only 372GB once installed?

Because windows uses the old definition of 1024B = 1KB, while hardware manufacturers use the reccomended SI definition of 1000B = 1KB.
 
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e-SATA notes and queries

Great guide, but does need to be extended to cover e-SATA as this does introduce cabling complications and further confusions. Some notes I've made from experience:
  1. e-SATA has a different (though very similar) data connector design and a different electrical specification aimed at allowing longer cable lengths.
  2. e-SATA is designed for external drive boxes which generally have their own power supply and a buffer chip between the e-SATA connector and the SATA hard drive inside.
  3. You can buy cables with SATA on one end and e-SATA on the other. These are often referred to incorrectly as SATA-I to SATA-II further ramping up the terminology confusion. In fact ordinary e-SATA to e-SATA cables are often labelled SATA-II which may be the source of the confusion regarding cable compatability between SATA-150 and SATA-300. Caveat emptor!
  4. You can connect an e-SATA external drive to a SATA port provided you keep to the SATA cable length restriction, not the e-SATA. There is a danger with building machines with SATA ports passively converted to e-SATA on the backplate. Subsequently you might use a full-length e-SATA cable to connect this to an external drive and it would be unreliable because the cable is not being driven at a high enough voltage.
  5. Some recent MBs have e-SATA connectors on their backplate (i.e. some of their available SATA ports are available only as e-SATA). This raises the question: can you connect a SATA internal drive directly to an e-SATA port? The electrical specification suggests this should be OK, but my experiments have not confirmed this. It seems that the higher drive voltage causes problems, at least for some HD models. I did not break any HD's but I could not get one to work reliably in this configuration.
  6. In Windows Vista, e-SATA HD's appear exactly as SATA ones and do not have the "safely remove" option that is available for USB external drives. Even though the specification claims to support "Hot Swapping", I cannot believe it is safe to simply whip the cable out no matter what Windows is doing at the time! How are you supposed to dismount these drives?
 
Associate
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ordering 2x wd raptor 150gig sata and 1 500gb sata2 caviar, will these work fine together? planning on having the 2 raptors in raid 0 and the 500gb sata 2 as storage.

Thanks
 
Associate
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Instead of making a thread ill ask here. What performance increase is there of using a Hard Drive with an 8mb cache over a 16mb cache?
 
Man of Honour
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Instead of making a thread ill ask here. What performance increase is there of using a Hard Drive with an 8mb cache over a 16mb cache?

The difference is likely to come more from improvements in drive technology for the 16mb cache drive rather than the level of cache itself, there will be some gain from the additional cache but it won't be as noticeable as the jump from 2mb to 8mb was. :)
 
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