Firewire -- on-board vs. add-on card -- performance the same?

[Igor]

I'm currently shopping for a socket AM2 motherboard that has both a
serial and a Firewire interface. I'd like the serial port so I can
plug in an external modem to use with Linux/BSD, while I figure that
the Firewire will probably be useful further down the road (though I
have no immediate need for it). What I'm finding is that several
motherboards in my price range ($60 to $120) have either one or the
other, but few are available that have both.

I've noticed that for $25 or thereabouts, you can buy a PCI card that
adds a Firewire interface to your PC. Though I'm not enthusiastic
about giving up a PCI slot (especially since many motherboards now
only give you two or three), I figure buying a board with just a
serial port and adding a PCI Firewire card when and if I need it might
be a solution. However, since these Firewire cards transfer data
through the PCI bus, I'm wondering: Do these add-on cards perform as
well as an on-board Firewire interface? Do Linux and BSD have any
problems recognizing these cards?

 

[david]

I'm currently shopping for a socket AM2 motherboard that has both a
serial and a Firewire interface. I'd like the serial port so I can plug
in an external modem to use with Linux/BSD, while I figure that the
Firewire will probably be useful further down the road (though I have no
immediate need for it). What I'm finding is that several motherboards in
my price range ($60 to $120) have either one or the other, but few are
available that have both.

I've noticed that for $25 or thereabouts, you can buy a PCI card that
adds a Firewire interface to your PC. Though I'm not enthusiastic about
giving up a PCI slot (especially since many motherboards now only give
you two or three), I figure buying a board with just a serial port and
adding a PCI Firewire card when and if I need it might be a solution.
However, since these Firewire cards transfer data through the PCI bus,
I'm wondering: Do these add-on cards perform as well as an on-board
Firewire interface? Do Linux and BSD have any problems recognizing these
cards?

It may still use the PCI bus, even if it's on board.

 

[kony]

I'm currently shopping for a socket AM2 motherboard that has both a
serial and a Firewire interface. I'd like the serial port so I can
plug in an external modem to use with Linux/BSD, while I figure that
the Firewire will probably be useful further down the road (though I
have no immediate need for it). What I'm finding is that several
motherboards in my price range ($60 to $120) have either one or the
other, but few are available that have both.

I've noticed that for $25 or thereabouts, you can buy a PCI card that
adds a Firewire interface to your PC. Though I'm not enthusiastic
about giving up a PCI slot (especially since many motherboards now
only give you two or three), I figure buying a board with just a
serial port and adding a PCI Firewire card when and if I need it might
be a solution. However, since these Firewire cards transfer data
through the PCI bus, I'm wondering: Do these add-on cards perform as
well as an on-board Firewire interface?

Yes, providing you don't have a lot of other concurrent PCI
traffic.

Do Linux and BSD have any
problems recognizing these cards?

That's a software question, more appropriately asked in a
group specific to the exact OS you want to run, not just a
general class of OS. Better to ask in such a forum "which
firewire chipsets have the best support".

If you have no immediate need, why are you thinking firewire
is important? BTW, there are PCIe firewire cards now. You
might seek some, note the chipset used, and Google for that
chipset + the specific OS you will use to find support
details.

 

[Ivan Marsh]

Do these add-on cards perform as well as an on-board Firewire interface?

No... The interface can only operate as fast as the bus it's plugged into
so assuming the hardwired bus is faster than PCI an add-on card will be
slower... but the performance difference probably won't be noticeable in
any case.

 

[dave]

No... The interface can only operate as fast as the bus it's plugged into
so assuming the hardwired bus is faster than PCI an add-on card will be
slower... but the performance difference probably won't be noticeable in
any case.

OpenBSD has no support for Firewire. This may be in part because the Firewire protocol
requires that the controller be able to access all of physical memory r/w, so it presents
a security problem.
--

 

[Ivan Marsh]

OpenBSD has no support for Firewire. This may be in part because the Firewire protocol
requires that the controller be able to access all of physical memory r/w, so it presents
a security problem.

Interesting... I did not know that.

Does OpenBSD support DMA on any device?

 

[Andrew Smallshaw]

[Newsgroups trimmed a little]

No... The interface can only operate as fast as the bus it's plugged into
so assuming the hardwired bus is faster than PCI an add-on card will be
slower... but the performance difference probably won't be noticeable in
any case.

Only in most cases the on-board firewire will be implemented on
the PCI bus anyway. Just because it isn't an expansion card doesn't
mean that it's not PCI.

In any case the point is moot as the PCI bus is higher bandwidth
than firewire. The PCI bus is only going to limit things if you
had a lot of other traffic on the bus, in which case the processor
is likely to be struggling to keep up.

Personally I prefer things like this to be off-board - expansion
cards are much more likely to detail what individual chips they
use so you can assess compatibility for any given OS. Even if you
have those details for the on-board option, you're more likely to
find specific compatibility reports for a card than you are for an
on-board implementation.

 

[kony]

No... The interface can only operate as fast as the bus it's plugged into
so assuming the hardwired bus is faster than PCI an add-on card will be
slower... but the performance difference probably won't be noticeable in
any case.

What in the world are you talking about?

The "interface", being firewire, is slower than the PCI bus.
There is no "assuming the hardwared bus is faster than PCI",
and why would you assume it, which seems rather crazy given
there are PCI firewire cards?

 

[AHappyCamper]

I'm currently shopping for a socket AM2 motherboard that has both a
serial and a Firewire interface. I'd like the serial port so I can
plug in an external modem to use with Linux/BSD, while I figure that
the Firewire will probably be useful further down the road (though I
have no immediate need for it). What I'm finding is that several
motherboards in my price range ($60 to $120) have either one or the
other, but few are available that have both.

I've noticed that for $25 or thereabouts, you can buy a PCI card that
adds a Firewire interface to your PC. Though I'm not enthusiastic
about giving up a PCI slot (especially since many motherboards now
only give you two or three), I figure buying a board with just a
serial port and adding a PCI Firewire card when and if I need it might
be a solution. However, since these Firewire cards transfer data
through the PCI bus, I'm wondering: Do these add-on cards perform as
well as an on-board Firewire interface? Do Linux and BSD have any
problems recognizing these cards?

Mepis 6.5-64bit on my system with the MSI K8NGM2-FID board/ AMD 939 pin
Sempron 3000+cpu, and 512MB RAM, (upgraded to 1.5Gb DDR 3200 RAM),
recognized everything fine, the add in PCI Firewire card runs great for
my 3 external drives.

kInfocenter reports the Actiontec, Initio, and MSI chipsets involved
under IEE-1394.

Mepis has the Debian, Ubuntu, and Mepis repositories for kSynaptic updates.

Install time for the new system, in May, was 9 minutes.
Full updates took another 20 minutes. All was automatic.
No problems since then, and my systems here all run 24/7/365.

 

[Ivan Marsh]

What in the world are you talking about?

The "interface", being firewire, is slower than the PCI bus. There is no
"assuming the hardwared bus is faster than PCI", and why would you
assume it, which seems rather crazy given there are PCI firewire cards?

Shorter path and less generic architecture = more efficient = faster...
though probably would have to be measured in nano seconds if not pico
seconds.

 

[dave]

[Newsgroups trimmed a little]

No... The interface can only operate as fast as the bus it's plugged into
so assuming the hardwired bus is faster than PCI an add-on card will be
slower... but the performance difference probably won't be noticeable in
any case.

Only in most cases the on-board firewire will be implemented on
the PCI bus anyway. Just because it isn't an expansion card doesn't
mean that it's not PCI.

In any case the point is moot as the PCI bus is higher bandwidth
than firewire. The PCI bus is only going to limit things if you
had a lot of other traffic on the bus, in which case the processor
is likely to be struggling to keep up.

PCIe is faster and more efficient than PCI. Maybe there are PCIe Firewire
cards available.

Personally I prefer things like this to be off-board - expansion
cards are much more likely to detail what individual chips they
use so you can assess compatibility for any given OS. Even if you
have those details for the on-board option, you're more likely to
find specific compatibility reports for a card than you are for an
on-board implementation.

--

 

[kony]

Shorter path and less generic architecture = more efficient = faster...
though probably would have to be measured in nano seconds if not pico
seconds.

PCI bus adds a bit of latency, but overall this is slight -
it'll still outperform USB2 for example. More significant
is contention on the bus with other PCI devices, if/when
applicable.

 

[Igor]

On Fri, 19 Oct 2007 16:36:21 +0000 (UTC), Andrew Smallshaw

In any case the point is moot as the PCI bus is higher bandwidth
than firewire. <snip>

Well, I think that's about as definitive an answer as I'll get. Case
closed!

Personally I prefer things like this to be off-board - expansion
cards are much more likely to detail what individual chips they
use so you can assess compatibility for any given OS. Even if you
have those details for the on-board option, you're more likely to
find specific compatibility reports for a card than you are for an
on-board implementation.

That's a smart buying strategy. It wouldn't have occurred to me to
look at it that way. I think I'll leave the Firewire off the board for
now, especially since a card will likely perform just as well and it
may not even be something I need.

 

[Igor]

If you have no immediate need, why are you thinking firewire
is important? <snip>

Echo Audio (http://echoaudio.com/) have been switching their line of
soundcards over to the Firewire interface.

I'm not necessarily going to buy one of their soundcards, but since
I'm building the PC from scratch, I may as well try to leave as many
options open as possible.

 

[Igor]

On Fri, 19 Oct 2007 15:15:16 -0500, dave

PCIe is faster and more efficient than PCI. Maybe there are PCIe Firewire
cards available.

I haven't seen any in the stores/catalogs I've looked through, but
that doesn't mean they're not out there. Even if they're not available
now, I'm sure they won't be long in coming.

That would actually work out well, since the PCI slots that are
disappearing from motherboards are frequently being replaced by PCIe
ones.

 

[Mark South]

Shorter path and less generic architecture = more efficient = faster...
though probably would have to be measured in nano seconds if not pico
seconds.

PCI bus is 133MHz, 32 or 64 bits wide, noticeably faster than firewire at
800Mb/s. Note that 1Gb/s is 1 bit per nanosecond. Picoseconds aren't
needed yet

Presumably onboard firewire is connected to the PCI bus anyway, or do you
know of a chipset that implements firewire on the northbridge?

 

[Scott Alfter]

In alt.comp.hardware.amd.x86-64 Andrew Smallshaw


PCIe is faster and more efficient than PCI. Maybe there are PCIe Firewire
cards available.

They are available. I have one in my MythTV box. It doesn't deliver any
performance increase, of course, as 400 Mbps is well below the maximum that
PCI or PCIe can deliver. It works as well as the previous PCI FireWire card
did.

(It did free up a PCI slot for another tuner, though...since tuner cards
that work with Linux aren't readily available for PCIe yet, this is a Good
Thing.)

_/_
/ v \ Scott Alfter (remove the obvious to send mail)
(IIGS( http://alfter.us/ Top-posting!
\_^_/ rm -rf /bin/laden >What's the most annoying thing on Usenet?

 

[kony]

Presumably onboard firewire is connected to the PCI bus anyway, or do you
know of a chipset that implements firewire on the northbridge?

A southbridge can also support non-PCI busses.

 

[Wolfie2k7]

I'm currently shopping for a socket AM2 motherboard that has both a
serial and a Firewire interface. I'd like the serial port so I can
plug in an external modem to use with Linux/BSD, while I figure that
the Firewire will probably be useful further down the road (though I
have no immediate need for it). What I'm finding is that several
motherboards in my price range ($60 to $120) have either one or the
other, but few are available that have both.

I've noticed that for $25 or thereabouts, you can buy a PCI card that
adds a Firewire interface to your PC. Though I'm not enthusiastic
about giving up a PCI slot (especially since many motherboards now
only give you two or three), I figure buying a board with just a
serial port and adding a PCI Firewire card when and if I need it might
be a solution. However, since these Firewire cards transfer data
through the PCI bus, I'm wondering: Do these add-on cards perform as
well as an on-board Firewire interface? Do Linux and BSD have any
problems recognizing these cards?

My 2 cents worth - Firewire is nice, but in all reality, there aren't
THAT many devices to connect with it. Camcorders, certain really
ancient (by modern standards) iPods, and maybe a few digital cameras
are about all that make use of the interface. There are a few external
hard drives that do as well - but for the most part, USB is as common
as dirt and pretty much everything I can think of will connect via
USB.

So - my advice would be to get a board that has LOTS of USB ports - 8
or more are a good thing. And if you get one that has standard PS/2
keyboard and mouse ports, you're that much further ahead in the game.