Serial ATA: Is it 1.5Gbps or 150MBps?

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

Built a new PC, used a single 160GB SATA drive. Noticed the drive said
"Serial ATA" with "1.5Gbps" under it. The software provided with the
motherboard confirmed this.

Why have I heard people quote it as 150MB/sec? If it is 1.5Gbps, where it
would be giga-bits, then it is either going to be 1500Mb/sec, or 1536Mb/sec
(depending on how they are determining what a gigabit is). Just converting
that to megabytes, you quickly see it is either 187MB/sec or 192MB/sec....
That's far from 150MB/sec. It seems the only way to get 1.5Gbps to come out
to 150MB/sec, is if a giga-bit = 1000 mega-bits, and 10 bits = 1 byte. That
is so wrong, I cannot imagine any forum would allow such measurments!

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

In article <MHFbc.61997$gA5.799763@attbi_s03>,
anonymousjoe@net.net says...
> Built a new PC, used a single 160GB SATA drive. Noticed the drive said
> "Serial ATA" with "1.5Gbps" under it. The software provided with the
> motherboard confirmed this.
>
> Why have I heard people quote it as 150MB/sec? If it is 1.5Gbps, where it
> would be giga-bits, then it is either going to be 1500Mb/sec, or 1536Mb/sec
> (depending on how they are determining what a gigabit is). Just converting
> that to megabytes, you quickly see it is either 187MB/sec or 192MB/sec....
> That's far from 150MB/sec. It seems the only way to get 1.5Gbps to come out
> to 150MB/sec, is if a giga-bit = 1000 mega-bits, and 10 bits = 1 byte. That
> is so wrong, I cannot imagine any forum would allow such measurments!
>
>

Well, typically when converting from bits to bytes on
serial transmissions, you allow a certain number of bits
as "overhead" anyway. (e.g. a 56kbps modem usually
delivered 5.6KB/s transfer rates, roughly 10 bits per
byte)

Also, the product is branded as SATA/150, not
SATA/1.5...

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

Anonymous Joe wrote:

> Built a new PC, used a single 160GB SATA drive. Noticed the drive said
> "Serial ATA" with "1.5Gbps" under it. The software provided with the
> motherboard confirmed this.

SATA is currently 150MB/sec. 1.5Gb/sec is just wrong.


-WD

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

Pretty much the same.

"Will Dormann" <wdormann@yahoo.com.invalid> wrote in message
news:eqJbc.3453$bP5.632@fe1.columbus.rr.com...
>
> SATA is currently 150MB/sec. 1.5Gb/sec is just wrong.
>
>
> -WD

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

In article <eqJbc.3453$bP5.632@fe1.columbus.rr.com>,
Will Dormann <wdormann@yahoo.com.invalid> wrote:
>Anonymous Joe wrote:
>
>> Built a new PC, used a single 160GB SATA drive. Noticed the drive said
>> "Serial ATA" with "1.5Gbps" under it. The software provided with the
>> motherboard confirmed this.
>
>SATA is currently 150MB/sec. 1.5Gb/sec is just wrong.
>
>
>-WD


1.5Gb is 120MB/sec. As far as marketing performance specs go, they are
close. Not that you'll see anything like this speed in a real system
for a long time. I just put a Maxtor 160GB SATA drive on an Asus
A7N8X mobo and HDtest showed 40MB/sec compared to 30MB/sec for a good
WD pata drive. (numbers from memory, don't quote me.)


--
Al Dykes
-----------
adykes at p a n i x . c o m

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

Unless my math is off, 1,500 / 8 = 187.5 MB/sec

Overstating is bad.

Tom

>
>
> 1.5Gb is 120MB/sec. As far as marketing performance specs go, they are
> close. Not that you'll see anything like this speed in a real system
> for a long time. I just put a Maxtor 160GB SATA drive on an Asus
> A7N8X mobo and HDtest showed 40MB/sec compared to 30MB/sec for a good
> WD pata drive. (numbers from memory, don't quote me.)
>
>
> --
> Al Dykes
> -----------
> adykes at p a n i x . c o m
>

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

Wrong. 1500Mb/10 is 150MB.

"Tom Scales" <tomtoo@softhome.net> wrote in message
news:7PednWA6_a58pO3dRVn-jg@comcast.com...
> Unless my math is off, 1,500 / 8 = 187.5 MB/sec
>
> Overstating is bad.
>

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

Toshi1873 <toshi1873@nowhere.com> wrote in message
news:MPG.1ad932be143e471198981c@news-50.giganews.com...
> anonymousjoe@net.net says...

>> Built a new PC, used a single 160GB SATA drive. Noticed
>> the drive said "Serial ATA" with "1.5Gbps" under it. The
>> software provided with the motherboard confirmed this.

>> Why have I heard people quote it as 150MB/sec? If it is 1.5Gbps, where it
>> would be giga-bits, then it is either going to be 1500Mb/sec, or 1536Mb/sec
>> (depending on how they are determining what a gigabit is). Just converting
>> that to megabytes, you quickly see it is either 187MB/sec or 192MB/sec....
>> That's far from 150MB/sec. It seems the only way to get 1.5Gbps to come
>> out to 150MB/sec, is if a giga-bit = 1000 mega-bits, and 10 bits = 1 byte.
>> That is so wrong, I cannot imagine any forum would allow such measurments!

> Well, typically when converting from bits to bytes on
> serial transmissions, you allow a certain number of bits
> as "overhead" anyway. (e.g. a 56kbps modem usually
> delivered 5.6KB/s transfer rates, roughly 10 bits per byte)

Thats due to a different effect, start and stop bit stripping.

> Also, the product is branded as SATA/150, not SATA/1.5...

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

Why in the world would you divide by 10?

There are EIGHT, count'em EIGHT (8) BITS in a BYTE.

You divide by 8.

Tom
"Eric Gisin" <ericgisin@graffiti.net> wrote in message
news:c4pg500ufl@enews4.newsguy.com...
> Wrong. 1500Mb/10 is 150MB.
>
> "Tom Scales" <tomtoo@softhome.net> wrote in message
> news:7PednWA6_a58pO3dRVn-jg@comcast.com...
> > Unless my math is off, 1,500 / 8 = 187.5 MB/sec
> >
> > Overstating is bad.
> >
>

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

"Tom Scales" <tomtoo@softhome.net> wrote in message
news:Rb6dnac4faaW_-3dRVn-hw@comcast.com...
> Why in the world would you divide by 10?
>
Because that's how 8 bits are encoded. Read the spec.

> There are EIGHT, count'em EIGHT (8) BITS in a BYTE.
>
> You divide by 8.
>
Nonsense.

> "Eric Gisin" <ericgisin@graffiti.net> wrote in message
> news:c4pg500ufl@enews4.newsguy.com...
> > Wrong. 1500Mb/10 is 150MB.

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

I'm not trying to start a fight, but there ARE 8 bits in a byte. Surely
you're joking that you think it is 10.

Tom
"Eric Gisin" <ericgisin@graffiti.net> wrote in message
news:c4pqju0r1@enews1.newsguy.com...
> "Tom Scales" <tomtoo@softhome.net> wrote in message
> news:Rb6dnac4faaW_-3dRVn-hw@comcast.com...
> > Why in the world would you divide by 10?
> >
> Because that's how 8 bits are encoded. Read the spec.
>
> > There are EIGHT, count'em EIGHT (8) BITS in a BYTE.
> >
> > You divide by 8.
> >
> Nonsense.
>
> > "Eric Gisin" <ericgisin@graffiti.net> wrote in message
> > news:c4pg500ufl@enews4.newsguy.com...
> > > Wrong. 1500Mb/10 is 150MB.
>

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

Any high-speed serial bus uses 10/8 encoding, 10 clocks per 8 data bits. It is
necessary to reduce high frequencies. I think FDDI was the first over 10 years
ago, then fast Ethernet.

"Tom Scales" <tomtoo@softhome.net> wrote in message
news:v66dnUtsftw-Fu3dRVn-tA@comcast.com...
> I'm not trying to start a fight, but there ARE 8 bits in a byte. Surely
> you're joking that you think it is 10.
>

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

"Toshi1873" <toshi1873@nowhere.com> wrote in message
news:MPG.1ad932be143e471198981c@news-50.giganews.com...
> In article <MHFbc.61997$gA5.799763@attbi_s03>,
> anonymousjoe@net.net says...
> > Built a new PC, used a single 160GB SATA drive. Noticed the drive said
> > "Serial ATA" with "1.5Gbps" under it. The software provided with the
> > motherboard confirmed this.
> >
> > Why have I heard people quote it as 150MB/sec? If it is 1.5Gbps, where
it
> > would be giga-bits, then it is either going to be 1500Mb/sec, or
1536Mb/sec
> > (depending on how they are determining what a gigabit is). Just
converting
> > that to megabytes, you quickly see it is either 187MB/sec or
192MB/sec....
> > That's far from 150MB/sec. It seems the only way to get 1.5Gbps to come
out
> > to 150MB/sec, is if a giga-bit = 1000 mega-bits, and 10 bits = 1 byte.
That
> > is so wrong, I cannot imagine any forum would allow such measurments!
> >
> >
>
> Well, typically when converting from bits to bytes on
> serial transmissions, you allow a certain number of bits
> as "overhead" anyway. (e.g. a 56kbps modem usually
> delivered 5.6KB/s transfer rates, roughly 10 bits per
> byte)
>
> Also, the product is branded as SATA/150, not
> SATA/1.5...

Ah, ok, that makes sense. I do have to say, though, that teh 160GB Maxtor
SATA I used did say "Serial ATA" and "1.5Gbps" under it. While that is not
explicity SATA/150 or SATA/1.5 either way, sure leads toward 1.5Gbps....

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

Tom Scales wrote:

> I'm not trying to start a fight, but there ARE 8 bits in a byte. Surely
> you're joking that you think it is 10.

Well, actually there are however many bits in a byte the machine designer
chose to put there. All the currently popular machines have 8-bit bytes so
8 bits has come to be assumed but there is nothing sacred about that
number.

When talking about data communications it's important to consider exactly
what you mean by "throughput". If you count every bit that goes down the
wire you get one number. If you discount the bits that carry the overhead
of the data-link protocol then you get another number. If you discount the
bits that carry the overhead of the transport protocol you get a third, and
so on. In data communications a byte is often assumed to be ten bits to
allow for protocol overhead and get a more realistic view of actual
throughput.


> Tom
> "Eric Gisin" <ericgisin@graffiti.net> wrote in message
> news:c4pqju0r1@enews1.newsguy.com...
>> "Tom Scales" <tomtoo@softhome.net> wrote in message
>> news:Rb6dnac4faaW_-3dRVn-hw@comcast.com...
>> > Why in the world would you divide by 10?
>> >
>> Because that's how 8 bits are encoded. Read the spec.
>>
>> > There are EIGHT, count'em EIGHT (8) BITS in a BYTE.
>> >
>> > You divide by 8.
>> >
>> Nonsense.
>>
>> > "Eric Gisin" <ericgisin@graffiti.net> wrote in message
>> > news:c4pg500ufl@enews4.newsguy.com...
>> > > Wrong. 1500Mb/10 is 150MB.
>>

--
--John
Reply to jclarke at ae tee tee global dot net
(was jclarke at eye bee em dot net)

 

[peter]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

A quick visit to www.serialata.org brings the following info:
1500MHz embedded clock
x 1 bit per clock
x 80% for 8b10b encoding
/ 8 bits per byte
= 150 Mbytes/sec
Key words are MHz, embedded clock, 8b10b encoding. Data is encoded/scrambled
to regenerate clock on receiver's end and to minimize RF emissions. No
wonder you get less data troughput than MHz number would suggest.

"Anonymous Joe" <anonymousjoe@net.net> wrote in message
news:MHFbc.61997$gA5.799763@attbi_s03...
> Built a new PC, used a single 160GB SATA drive. Noticed the drive said
> "Serial ATA" with "1.5Gbps" under it. The software provided with the
> motherboard confirmed this.
>
> Why have I heard people quote it as 150MB/sec? If it is 1.5Gbps, where it
> would be giga-bits, then it is either going to be 1500Mb/sec, or
1536Mb/sec
> (depending on how they are determining what a gigabit is). Just
converting
> that to megabytes, you quickly see it is either 187MB/sec or 192MB/sec....
> That's far from 150MB/sec. It seems the only way to get 1.5Gbps to come
out
> to 150MB/sec, is if a giga-bit = 1000 mega-bits, and 10 bits = 1 byte.
That
> is so wrong, I cannot imagine any forum would allow such measurments!
>
>
>

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

Previously Will Dormann <wdormann@yahoo.com.invalid> wrote:
> Anonymous Joe wrote:

>> Built a new PC, used a single 160GB SATA drive. Noticed the drive said
>> "Serial ATA" with "1.5Gbps" under it. The software provided with the
>> motherboard confirmed this.

> SATA is currently 150MB/sec. 1.5Gb/sec is just wrong.

b = bit, B = Byte.

Arno
--
For email address: lastname AT tik DOT ee DOT ethz DOT ch
GnuPG: ID:1E25338F FP:0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F
"The more corrupt the state, the more numerous the laws" - Tacitus

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

"Tom Scales" <tomtoo@softhome.net> wrote in message news:Rb6dnac4faaW_-3dRVn-hw@comcast.com
> Why in the world would you divide by 10?
>
> There are EIGHT, count'em EIGHT (8) BITS in a BYTE.

Yup. Pity that bytes aren't sent over a serial interface, but bits.
With modems you used to call them "baud". Depending on (lengtht of) start and
(number of) stopbits you divide by between 9 to 11.5 for the number of bytes.

>
> You divide by 8.

Nope.

>
> Tom
> "Eric Gisin" <ericgisin@graffiti.net> wrote in message news:c4pg500ufl@enews4.newsguy.com...
> > Wrong. 1500Mb/10 is 150MB.
> >
> > "Tom Scales" tomtoo@softhome.net> wrote in message news:7PednWA6_a58pO3dRVn-jg@comcast.com...
> > > Unless my math is off, 1,500 / 8 = 187.5 MB/sec
> > >
> > > Overstating is bad.

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

"J. Clarke" <jclarke@nospam.invalid> wrote in message news:c4q9aj010m6@news3.newsguy.com
> Tom Scales wrote:
>
> > I'm not trying to start a fight, but there ARE 8 bits in a byte. Surely
> > you're joking that you think it is 10.
>
> Well, actually there are however many bits in a byte the machine designer
> chose to put there. All the currently popular machines have 8-bit bytes so
> 8 bits has come to be assumed but there is nothing sacred about that number.

That may be so for words, but not bytes.
The PDP* had 12-bit words but a byte was still 8 bits, afaik.

>
> When talking about data communications it's important to consider exactly
> what you mean by "throughput". If you count every bit that goes down the
> wire you get one number. If you discount the bits that carry the overhead
> of the data-link protocol then you get another number. If you discount the
> bits that carry the overhead of the transport protocol you get a third, and
> so on. In data communications a byte is often assumed to be ten bits to
> allow for protocol overhead and get a more realistic view of actual throughput.
>
>
> > Tom
> > "Eric Gisin" ericgisin@graffiti.net> wrote in message news:c4pqju0r1@enews1.newsguy.com...
> > > "Tom Scales" tomtoo@softhome.net> wrote in message news:Rb6dnac4faaW_-3dRVn-hw@comcast.com...
> > > > Why in the world would you divide by 10?
> > > >
> > > Because that's how 8 bits are encoded. Read the spec.
> > >
> > > > There are EIGHT, count'em EIGHT (8) BITS in a BYTE.
> > > >
> > > > You divide by 8.
> > > >
> > > Nonsense.
> > >
> > > > "Eric Gisin" ericgisin@graffiti.net> wrote in message news:c4pg500ufl@enews4.newsguy.com...
> > > > > Wrong. 1500Mb/10 is 150MB.

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

"J. Clarke" <jclarke@nospam.invalid> wrote in message news:c4q9aj010m6@news3.newsguy.com
> Tom Scales wrote:
>
> > I'm not trying to start a fight, but there ARE 8 bits in a byte. Surely
> > you're joking that you think it is 10.
>
> Well, actually there are however many bits in a byte the machine designer
> chose to put there. All the currently popular machines have 8-bit bytes so
> 8 bits has come to be assumed but there is nothing sacred about that number.

That may be so for words, but not bytes.
The PDP* had 12-bit words but a byte was still 8 bits, afaik.

>
> When talking about data communications it's important to consider exactly
> what you mean by "throughput". If you count every bit that goes down the
> wire you get one number. If you discount the bits that carry the overhead
> of the data-link protocol then you get another number. If you discount the
> bits that carry the overhead of the transport protocol you get a third, and
> so on. In data communications a byte is often assumed to be ten bits to
> allow for protocol overhead and get a more realistic view of actual throughput.
>
>
> > Tom
> > "Eric Gisin" ericgisin@graffiti.net> wrote in message news:c4pqju0r1@enews1.newsguy.com...
> > > "Tom Scales" tomtoo@softhome.net> wrote in message news:Rb6dnac4faaW_-3dRVn-hw@comcast.com...
> > > > Why in the world would you divide by 10?
> > > >
> > > Because that's how 8 bits are encoded. Read the spec.
> > >
> > > > There are EIGHT, count'em EIGHT (8) BITS in a BYTE.
> > > >
> > > > You divide by 8.
> > > >
> > > Nonsense.
> > >
> > > > "Eric Gisin" ericgisin@graffiti.net> wrote in message news:c4pg500ufl@enews4.newsguy.com...
> > > > > Wrong. 1500Mb/10 is 150MB.

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

In article <c4uvid$2o5760$5@ID-79662.news.uni-berlin.de>,
Folkert Rienstra <folkertdotrienstra@freeler.nl> wrote:
>"J. Clarke" <jclarke@nospam.invalid> wrote in message news:c4q9a
j010m6@news3.newsguy.com
>> Tom Scales wrote:
>>
>> > I'm not trying to start a fight, but there ARE 8 bits in a byte. Surely
>> > you're joking that you think it is 10.
>>
>> Well, actually there are however many bits in a byte the machine designer
>> chose to put there. All the currently popular machines have 8-bit bytes so
>> 8 bits has come to be assumed but there is nothing sacred about that number.
>
>That may be so for words, but not bytes.
>The PDP* had 12-bit words but a byte was still 8 bits, afaik.
>

From the Jargon File (aka The New hacker's Dictionary)

byte /bi:t/ n.

[techspeak] A unit of memory or data equal to the amount used to
represent one character; on modern architectures this is usually 8
bits, but may be 9 on 36-bit machines. Some older architectures used
`byte' for quantities of 6 or 7 bits, and the PDP-10 supported `bytes'
that were actually bitfields of 1 to 36 bits! These usages are now
obsolete, and even 9-bit bytes have become rare in the general trend
toward power-of-2 word sizes.

Historical note: The term was coined by Werner Buchholz in 1956 during
the early design phase for the IBM Stretch computer; originally it was
described as 1 to 6 bits (typical I/O equipment of the period used
6-bit chunks of information). The move to an 8-bit byte happened in
late 1956, and this size was later adopted and promulgated as a
standard by the System/360. The word was coined by mutating the word
`bite' so it would not be accidentally misspelled as bit. See also
nybble.


Does this put an end to this thread, please ?

>>
>> When talking about data communications it's important to consider exactly
>> what you mean by "throughput". If you count every bit that goes down the
>> wire you get one number. If you discount the bits that carry the overhead
>> of the data-link protocol then you get another number. If you discount the
>> bits that carry the overhead of the transport protocol you get a third, and
>> so on. In data communications a byte is often assumed to be ten bits to
>> allow for protocol overhead and get a more realistic view of actual
>>throughput.
>>
>>
>> > Tom
>> > "Eric Gisin" ericgisin@graffiti.net> wrote in message
>> > news:c4pqju0r1@enews1.newsguy.com...
>> > > "Tom Scales" tomtoo@softhome.net> wrote in message news:Rb6dna
>> > > c4faaW_-3dRVn-hw@comcast.com...
>> > > > Why in the world would you divide by 10?
>> > > >
>> > > Because that's how 8 bits are encoded. Read the spec.
>> > >
>> > > > There are EIGHT, count'em EIGHT (8) BITS in a BYTE.
>> > > >
>> > > > You divide by 8.
>> > > >
>> > > Nonsense.
>> > >
>> > > > "Eric Gisin" ericgisin@graffiti.net> wrote in
>> > > > message news:c4pg500ufl@enews4.newsguy.com...
>> > > > > Wrong. 1500Mb/10 is 150MB.


--
Al Dykes
-----------
adykes at p a n i x . c o m

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

Folkert Rienstra <see_reply-to@myweb.nl> wrote in message
news:c4uvic$2o5760$4@ID-79662.news.uni-berlin.de...
> Tom Scales <tomtoo@softhome.net> wrote

>> Why in the world would you divide by 10?

>> There are EIGHT, count'em EIGHT (8) BITS in a BYTE.

> Yup. Pity that bytes aren't sent over a serial interface, but bits.

> With modems you used to call them "baud".

For a different concept.

> Depending on (lengtht of) start and (number of) stopbits

Mangled all over again.

> you divide by between 9 to 11.5 for the number of bytes.

>> You divide by 8.

> Nope.


> > "Eric Gisin" <ericgisin@graffiti.net> wrote in message news:c4pg500ufl@enews4.newsguy.com...
> > > Wrong. 1500Mb/10 is 150MB.
> > >
> > > "Tom Scales" tomtoo@softhome.net> wrote in message news:7PednWA6_a58pO3dRVn-jg@comcast.com...
> > > > Unless my math is off, 1,500 / 8 = 187.5 MB/sec
> > > >
> > > > Overstating is bad.

 

[Nuke]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

>Anonymous Joe wrote:
>
>> Built a new PC, used a single 160GB SATA drive. Noticed the drive said
>> "Serial ATA" with "1.5Gbps" under it. The software provided with the
>> motherboard confirmed this.
>
>SATA is currently 150MB/sec. 1.5Gb/sec is just wrong.
>

The correct figure by specification is indeed 1.5 gigabits per second.

Serial ATA I always runs at this speed.

This corresponds with a parallel ATA figure of 150 mega-bytes per second. Some
of the bits are consumed in encoding. Parallel ATA has always figured rates
based on maximum data throughput during the clocking of 16-bit words across the
interface.
--
Dr. Nuketopia
Sorry, no e-Mail.
Spam forgeries have resulted in thousands of faked bounces to my address.

 

[Guest]

Archived from groups: comp.sys.ibm.pc.hardware.storage (More info?)

"nuke" <larrysb@aol.commode> wrote in message news:20040415170550.12763.00000228@mb-m24.aol.com
> > Anonymous Joe wrote:
> >
> > > Built a new PC, used a single 160GB SATA drive. Noticed the drive said
> > > "Serial ATA" with "1.5Gbps" under it. The software provided with the
> > > motherboard confirmed this.
> >
> > SATA is currently 150MB/sec. 1.5Gb/sec is just wrong.
> >
>
> The correct figure by specification is indeed 1.5 gigabits per second.
>
> Serial ATA I always runs at this speed.
>
> This corresponds with a parallel ATA figure of 150 mega-bytes per second.

Nope.

> Some of the bits are consumed in encoding.

Yes, two out of 10 of them, obviously.

The Serial protocol will take several bytes off of that and leave less than
150MB/s. Then the ATA protocol will do the same and leave even less.

> Parallel ATA has always figured rates based on maximum data
> throughput during the clocking of 16-bit words across the interface.

Right, but those type of figures are misleading as the datarate of the bus
is not the same as the user data rate since command overhead and protocol overhead take their own bite out of that.