CNR

[DukeChestnut]

are CNRs any good? i've never seen a CNR nic b4. anyone ever use one? is it inferior to a pci nic?

 

[Tanked]

CNR networking cards might be ok, but CNR Modems are software based, while PCI modems can be either way. CNR sound cards are also usually software based.

 

[DukeChestnut]

CNR networking cards might be ok

do u know if theres a difference in performance between a CNR and PCI port?

 

[AndyHui]

If anything, a CNR NIC should be better than a PCI NIC.

Most chipsets, such as any Intel with ICH2, ICH3 and ICH4, all have an NIC built into the South Bridge. A CNR merely provides an RJ-45 socket. This NIC does not need a PCI slot, and does not share PCI slot bandwidth either, as it goes directly over the Hub Link.

 

[DukeChestnut]

w00t w00t! thanx andy thats all i needed to hear.

 

[Peter]

Not quite, Andy. The chipset integrated LAN stuff that feeds the CNR slot is a MAC only (the LAN engine). The CNR riser has the PHYsical interface chip, transformer and of course RJ45.

Same with CNR or AMR modems - the data pump is in the chipset, the physical interface codec and line interface stuff is on the riser card.

You're right about the PCI bandwidth usage thing though and yes, chipset integrated LAN is no worse in CPU usage than PCI LAN, and since it's on a fast chipset internal bus, bus bandwidth usage is lower.

Yes, AMR or CNR modems are CPU driven softmodems - but given the speed of today's CPUs, noone will notice. The only thing one does notice is the high roundtrip delay aka "ping latency".

regards, Peter

 

[AndyHui]

You're right. I neglected to mention the PHY because I wasn't too sure on that. Thanks Peter.

The PHY doesn't affect performance, does it?

 

[Peter]

Same as with audio - you need to have a digital-to-analog conversion somewhere. On LAN you call that a PHY (and typically connect to the MAC through an MII or RMII digital bus), on audio you call it codec (and typically connect to the sound engine through an AC97 digital bus).

Some LAN chips integrate MAC and PHY, just as some audio chips integrate engine and codec. Integrated or separate says nothing about how much bus or CPU time the device uses - THAT is all in the MAC or sound engine's hardware capabilities or lack thereof.

Remember my frequently repeated rant about the fact that "AC97 sound" means exactly nothing, and that reviewers should quit spreading that nonsense? SB!Audigy uses AC97 bus and codecs just as well as Intel 810 audio does. Intro the FAQ please.

regards, Peter

 

[DukeChestnut]

sweeeeeeeeeeeet! so i'm golden by using a CNR NIC? or at least no better off than PCI?

 

[SuperSix]

I use a Hercules CNR sound card, It uses the same ADI 1885 AC97 codecs as the sound onboard, just more of them. The CNR provides rear and sub channels, the built0in ports handle the front speakers.

Intel makes Server-class CNR NICs, but I haven't seen any entry level ones yet.

 

[DukeChestnut]

super6 try this LINKY

 

[DukeChestnut]

i just ordered one so i hope it performs well.