AGP speed 2X,4x,8X: What it really means!

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Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>I'm running a hard drive on a 36" round IDE cable with no problems. I needed
>it
>because it's a full tower case so the cable will reach. DOUG

The 18" is just a spec, it doesn't mean longer won't work but there is a risk
of having data corruption.
--------------------------------------------------------------------------
---------------------------------
Apparently a useless spec.
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

Courseyauto wrote:

>>I'm running a hard drive on a 36" round IDE cable with no problems. I
>>needed it
>>because it's a full tower case so the cable will reach. DOUG
>
> The 18" is just a spec, it doesn't mean longer won't work but there is a
> risk of having data corruption.
> --------------------------------------------------------------------------
> ---------------------------------
> Apparently a useless spec.

The spec is what the designers work to. To get reliable operation they put
in some margin, so you can get away with a slightly longer cable or one
that is slightly out of spec or whatever, but it's not something you should
count on.

--
--John
Reply to jclarke at ae tee tee global dot net
(was jclarke at eye bee em dot net)
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

PRIVATE1964 wrote:

>>
>>And that's the only real benefit of SATA that I can see that is inherent
>>in its being serial--that narrow cable is a lot easier to route.
>
> Here's a question for you that will keep me from having to search on
> related to SATA. I plan on getting a new serial hard drive soon.
>
> I'm using a NF7-S with serial connections.
> What is the maximum throughput for a hard drive connected to the serial
> connection.
>
> Is that connection spec'd for 150Mb/sec? I've read that the serial drives
> that are out now are not "true native" serial drives so there is no way
> they could ever hit 150Mb/sec.
>
> What can you tell me about this please.

There is no drive in the world that can fill a 100 MB/sec pipe. WD Raptors
have a maximum sustained transfer rate of 72 MB/sec, 7K400s max at 62.1,
Cheetah X15s max at 86. The limit is the bits per track and the rotational
speed, not the interface. So it doesn't matter whether the interface can
hit 150 or 133 or 100.

With PATA and two drives per channel, it's possible for both drives together
to fill a 150 MB/sec channel but SATA allows only one per channel so that's
not an issue.

In any case, some use a bridge chip, others don't. IIRC Seagate is not
using a bridge chip. I don't recall what WD is doing, but their Raptors
outperform any SATA drive from any other manufacturer, although the Hitachi
7K250 and 7K400 come close, so whether they're using a bridge chip or not
clearly doesn't make any real-world difference.

>
> Thanks

--
--John
Reply to jclarke at ae tee tee global dot net
(was jclarke at eye bee em dot net)
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>Apparently a useless spe

Not really I guess it depends on how much you value your data though. Because
It only takes one time to lose everything.
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>Apparently a useless spe

Not really I guess it depends on how much you value your data though. Because
It only takes one time to lose everything.

--------------------------------------------------------------------------
--------------------------------
Hanv't lost a thing yet in 2 years since i built it,whens it gonna happen?
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

Courseyauto wrote:

>>Apparently a useless spe
>
> Not really I guess it depends on how much you value your data though.
> Because It only takes one time to lose everything.
>
> --------------------------------------------------------------------------
> --------------------------------
> Hanv't lost a thing yet in 2 years since i built it,whens it gonna happen?

When you can least afford it to of course.

--
--John
Reply to jclarke at ae tee tee global dot net
(was jclarke at eye bee em dot net)
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>Hanv't lost a thing yet in 2 years since i built it,whens it gonna happen?

I honestly don't know, but if it happens a year from now you will lose even
more data then you have now.

It only takes once.
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

"J. Clarke" <jclarke@nospam.invalid> wrote in message
news:cithok02vi2@news1.newsguy.com...
> PRIVATE1964 wrote:
>
> >>
> >>And that's the only real benefit of SATA that I can see that is inherent
> >>in its being serial--that narrow cable is a lot easier to route.
> >
> > Here's a question for you that will keep me from having to search on
> > related to SATA. I plan on getting a new serial hard drive soon.
> >
> > I'm using a NF7-S with serial connections.
> > What is the maximum throughput for a hard drive connected to the serial
> > connection.
> >
> > Is that connection spec'd for 150Mb/sec? I've read that the serial
drives
> > that are out now are not "true native" serial drives so there is no way
> > they could ever hit 150Mb/sec.
> >
> > What can you tell me about this please.
>
> There is no drive in the world that can fill a 100 MB/sec pipe. WD
Raptors
> have a maximum sustained transfer rate of 72 MB/sec, 7K400s max at 62.1,
> Cheetah X15s max at 86. The limit is the bits per track and the
rotational
> speed, not the interface. So it doesn't matter whether the interface can
> hit 150 or 133 or 100.

.... apart from the burst speed which with drives with 16MB cache now can be
a significant factor, especially with video editing applications (where the
caching algorithms have a better chance because of the big files). 16MB
bursting at 150MB/s is not insigificant.

> With PATA and two drives per channel, it's possible for both drives
together
> to fill a 150 MB/sec channel but SATA allows only one per channel so
that's
> not an issue.
>
> In any case, some use a bridge chip, others don't. IIRC Seagate is not
> using a bridge chip. I don't recall what WD is doing, but their Raptors
> outperform any SATA drive from any other manufacturer, although the
Hitachi
> 7K250 and 7K400 come close, so whether they're using a bridge chip or not
> clearly doesn't make any real-world difference.

The Raptors have a bridge chip too. They are basically SCSI drives with an
adapter chip on them.

Chip
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

Chip wrote:

>
> "J. Clarke" <jclarke@nospam.invalid> wrote in message
> news:cithok02vi2@news1.newsguy.com...
>> PRIVATE1964 wrote:
>>
>> >>
>> >>And that's the only real benefit of SATA that I can see that is
>> >>inherent in its being serial--that narrow cable is a lot easier to
>> >>route.
>> >
>> > Here's a question for you that will keep me from having to search on
>> > related to SATA. I plan on getting a new serial hard drive soon.
>> >
>> > I'm using a NF7-S with serial connections.
>> > What is the maximum throughput for a hard drive connected to the serial
>> > connection.
>> >
>> > Is that connection spec'd for 150Mb/sec? I've read that the serial
> drives
>> > that are out now are not "true native" serial drives so there is no way
>> > they could ever hit 150Mb/sec.
>> >
>> > What can you tell me about this please.
>>
>> There is no drive in the world that can fill a 100 MB/sec pipe. WD
> Raptors
>> have a maximum sustained transfer rate of 72 MB/sec, 7K400s max at 62.1,
>> Cheetah X15s max at 86. The limit is the bits per track and the
> rotational
>> speed, not the interface. So it doesn't matter whether the interface can
>> hit 150 or 133 or 100.
>
> ... apart from the burst speed which with drives with 16MB cache now can
> be a significant factor, especially with video editing applications (where
> the
> caching algorithms have a better chance because of the big files). 16MB
> bursting at 150MB/s is not insigificant.

I fail to see how it makes a difference with video editing, where you are
trying to stream several gigabytes of data.

How much real-world difference do you see between a drive with a 16 meg
cache and an otherwise identical drive with a 2 meg cache?

>> With PATA and two drives per channel, it's possible for both drives
> together
>> to fill a 150 MB/sec channel but SATA allows only one per channel so
> that's
>> not an issue.
>>
>> In any case, some use a bridge chip, others don't. IIRC Seagate is not
>> using a bridge chip. I don't recall what WD is doing, but their Raptors
>> outperform any SATA drive from any other manufacturer, although the
> Hitachi
>> 7K250 and 7K400 come close, so whether they're using a bridge chip or not
>> clearly doesn't make any real-world difference.
>
> The Raptors have a bridge chip too. They are basically SCSI drives with
> an adapter chip on them.

I see. So you are claiming that they have a SCSI interface bridged to SATA?
Or are you just saying that being constructed to the same quality standards
as server-grade drives somehow makes them have a different interface?
>
> Chip

--
--John
Reply to jclarke at ae tee tee global dot net
(was jclarke at eye bee em dot net)
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

"Courseyauto" <courseyauto@aol.com> wrote in message
news:20040922191133.29600.00001154@mb-m29.aol.com...
> >I'm running a hard drive on a 36" round IDE cable with no problems. I
needed
> >it
> >because it's a full tower case so the cable will reach. DOUG
>
> The 18" is just a spec, it doesn't mean longer won't work but there is a
risk
> of having data corruption.
> --------------------------------------------------------------------------
> ---------------------------------
> Apparently a useless spec.

Like XP2500's specced to run at 1733 MHz when they will all do 2133? or
GF6800GT's specced to run at 350MHz when they will all do 375+ or perhaps
400+ or 425+ or
Memory that's specced to run 200MHz but will actually do 220MHz

Come on, a spec is just a spec. The manufacturer has to build in some
"slack" so that they don't get lots of problems in the field. They want
some comfort built in, so that their components still perform in less than
ideal conditions. So if you have better conditions, you can oftern exceed
the spec.

That's just the way the world is. Its not a useless spec.

Chip
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

Chip wrote:

>
> "Courseyauto" <courseyauto@aol.com> wrote in message
> news:20040922191133.29600.00001154@mb-m29.aol.com...
>> >I'm running a hard drive on a 36" round IDE cable with no problems. I
> needed
>> >it
>> >because it's a full tower case so the cable will reach. DOUG
>>
>> The 18" is just a spec, it doesn't mean longer won't work but there is a
> risk
>> of having data corruption.
>>
--------------------------------------------------------------------------
>> ---------------------------------
>> Apparently a useless spec.
>
> Like XP2500's specced to run at 1733 MHz when they will all do 2133? or
> GF6800GT's specced to run at 350MHz when they will all do 375+ or perhaps
> 400+ or 425+ or
> Memory that's specced to run 200MHz but will actually do 220MHz
>
> Come on, a spec is just a spec. The manufacturer has to build in some
> "slack" so that they don't get lots of problems in the field.

Also to reduce their reject rate at the factory. If they designed the
XP2500s to run at exactly 1733 MHz they'd end up rejecting half their
production.

> They want
> some comfort built in, so that their components still perform in less than
> ideal conditions. So if you have better conditions, you can oftern exceed
> the spec.
>
> That's just the way the world is. Its not a useless spec.
>
> Chip

--
--John
Reply to jclarke at ae tee tee global dot net
(was jclarke at eye bee em dot net)
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>The spec is what the designers work to. To get reliable operation they put
>in some margin, so you can get away with a slightly longer cable or one
>that is slightly out of spec or whatever, but it's not something you should
>count on.
>

Totally agree.

They design for probably worse case scenario. So he might never have any
problems or one day he could lose everything.
Like I posted it all depends on how much you value your personal data like
family pictures, spread sheets, word documents, porn etc.
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

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

Thanks. I realize they could never hit 150Mb sustained, but is it possible for
150Mb burst with those sata connections on the NF7-S?
If you have a drive even if in the future that is capable of 150Mbs burst speed
can the NF7-S connections support that speed?
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>where the
>caching algorithms have a better chance because of the big files). 16MB
>bursting at 150MB/s is not insigificant.

Do the NF7-S sata connections support 150Mb burst speed?
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>When you can least afford it to of course.
>

Isn't that always the case.
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>where the
>caching algorithms have a better chance because of the big files). 16MB
>bursting at 150MB/s is not insigificant.

<Do the NF7-S sata connections support 150Mb burst speed?

They are on the PCI buss,so what do you think?
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>
> They are on the PCI buss,so what do you think?

I don't know that's why I asked. Maybe you could explain it in some detail.
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>
> They are on the PCI buss,so what do you think?

I don't know that's why I asked. Maybe you could explain it in some detail.

--------------------------------------------------------------------------
--------------------------

In detail it will run at PCI buss speed,and you know what that is.
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>In detail it will run at PCI buss speed,and you know what that is.

I honestly I don't know the maximum bandwith of the PCI bus.

Do I have to beg to get the answer?
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>In detail it will run at PCI buss speed,and you know what that is.

I honestly I don't know the maximum bandwith of the PCI bus.

Do I have to beg to get the answer?

--------------------------------------------------------------------------
------------------
133mbs
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

Courseyauto wrote:

>
>>In detail it will run at PCI buss speed,and you know what that is.
>
> I honestly I don't know the maximum bandwith of the PCI bus.
>
> Do I have to beg to get the answer?
>
> --------------------------------------------------------------------------
> ------------------
> 133mbs

No, 133 MB/sec. MegaBytes, not millibits. While the m isn't
serious--nobody with a clue would make that mistake, the b vs B is a
different story--bits vs bytes.

--
--John
Reply to jclarke at ae tee tee global dot net
(was jclarke at eye bee em dot net)
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>133mbs

So then the SATA connections don't even support 150Mb/s. Isn't that a
requirement of the specs that they support 150Mb/s?
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>No, 133 MB/sec. MegaBytes, not millibits. While the m isn't
>serious--nobody with a clue would make that mistake, the b vs B is a
>different story--bits vs bytes.

Let me see if I have this right.

The PCI bus can support 133MB/sec, but the SATA supports 150Mb/sec. So there is
plenty of bandwith on the PCI bus for the SATA connections right?
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

PRIVATE1964 wrote:

>>No, 133 MB/sec. MegaBytes, not millibits. While the m isn't
>>serious--nobody with a clue would make that mistake, the b vs B is a
>>different story--bits vs bytes.
>
> Let me see if I have this right.
>
> The PCI bus can support 133MB/sec, but the SATA supports 150Mb/sec. So
> there is plenty of bandwith on the PCI bus for the SATA connections right?

The PCI bus has a theoretical maximum throughput of 32x33e6 or 1,056,000,000
bits/sec or 132,000,000 bytes per second. SATA has a theoretical maximum
throughput of 150,000,000 bytes per second. So to answer you question, no,
there is not plenty of bandwidth on the PCI bus. For now it's moot since no
drive provides sustained transfers in excess of 100. Running RAID it's
quite possible to saturate the PCI bus. That's why PCI-X and PCI Express
exist and why servers are often made with more than one PCI bus.

--
--John
Reply to jclarke at ae tee tee global dot net
(was jclarke at eye bee em dot net)
 
Archived from groups: alt.comp.periphs.videocards.nvidia (More info?)

>The PCI bus has a theoretical maximum throughput of 32x33e6 or 1,056,000,000
>bits/sec or 132,000,000 bytes per second. SATA has a theoretical maximum
>throughput of 150,000,000 bytes per second. So to answer you question, no,
>there is not plenty of bandwidth on the PCI bus. For now it's moot since no
>drive provides sustained transfers in excess of 100. Running RAID it's
>quite possible to saturate the PCI bus. That's why PCI-X and PCI Express
>exist and why servers are often made with more than one PCI bus.
>

OK that clears up what I wanted to know very well. Thanks to you and everyone
else.

How much does the burst rate matter in the scheme of things? How often does a
drive hit that burst rate speed?