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Is CSA integrated LAN an issue if one uses a PCI NIC card?

C

computer

Platinum Member
Does anyone know if CSA for integrated LAN is an issue if one uses a PCI NIC card (Intel gigabit PRO1000MT)? I've heard a NON CSA LAN chip can hog/slow down the PCI bus, so I'm wondering of this PCI NIC would do the same thing in a NON CSA 865/875 mobo.
Thanks.
 
Thanks. Even if it's the above mentioned NIC? This is I assume the same chipset that the CSA mobo's are using, the Intel Pro Gigabit. And if it is, I'm thinking it may have some kind of (for lack of a better term) "on board NIC processor" on the card. Sort of, so to speak like a hardware modem Vs. a winmodem. ?
 
Sure is. The point is that a Gbit Ethernet connection needs about 250 MB/s bus bandwidth. On standard commodity 32-bit/33 MHz PCI, you have about 100 MB/s TOTAL bandwidth. How's that supposed to work well? Guess why Gbit Ethernet PCI cards are 64-bit PCI and/or 66 MHz capable ...

CSA is no miracle technology, just a dedicated connection for a single GBE chip, providing enough bandwidth and leaving that creepingly slow PCI bus alone.

That's why you won't find CSA on a serious mainboard - you got fast PCI busses there, so why bother? This is where your PCI GBE NIC should find a home.
 
That's why you won't find CSA on a serious mainboard ...
Click to expand...

The best 875 mobo's have CSA (IC7-G, 8KNXP, 875 Neo2 FISR2, etc). Not sure what you meant by that.

So Peter, I'm not clear on what you were saying "Sure is" to......sorry. So you're saying that if I used that NIC (BTW, it's a 66mhz PCI) on a NON CSA mobo and disabled the integrated NIC, it would be just like a NON CSA mobo, or it would be like I described with the hardware modem Vs Winmodem analogy, and be like a CSA supported mobo?

Thanks. 🙂
 
When Peter mentioned a "serious" motherboard I'm pretty sure he was referring to more server oriented boards that already have faster PCI busses (64bit/66Mhz) which wouldn't need the Intel CSA bus to get full GbE bandwidth.

Whether you have a motherboard with CSA or not will make absolutely no difference if you toss in a PCI NIC. The CSA is a dedicated bus between the onboard NIC and the 865/875 chipset. If you stick a PCI NIC in there, that NIC will be using the PCI bus.

Gaidin
 
Once again. CSA is not a miracle technology that accelerates PCI NICs. It is a dedicated connection to a special onboard GBE chip.
Your PCI NIC may be 66 MHz capable, but the PCI bus offered on commodity chipsets is not. The 875 is no better in that regard.
This is what CSA is about - allowing a single full speed GBE channel without having to implement faster PCI busses.
 
Yes I know what "CSA" is. 🙂 I was trying to determine if an Intel PRO1000 Gigabit PCI NIC would circumvent the shortcomings of a non CSA mobo. Evidently not, which makes perfect sense. I was leaning towards that (since the NIC is obviously using a PCI slot), but wanted to know for SURE. Thanks Gaidin & Peter.

Non CSA mobo's have as good as, and sometimes better performance than a CSA mobo according to the tests. Has anyone seen any tests run when their PCI slots are in use, or with the NON CSA LAN ENABLED and IN USE? I would be very interested to know if the performance is still the same, or if it would suffer on a non CSA board.
 
If you have the infrastructure to feed the Gbit Ethernet full throttle, there's no way a standard PCI bus at around 100 to 110 MByte/s can cope with the amount of data to be shifted - not even in one direction, let alone full duplex.

That's why serious Gbit ethernet cards are 64-bit and/or 66 MHz PCI, and this is also why CSA got invented for chipsets that have only 32-bit 33 MHz PCI.
 
Peter, see this please:

Are you saying that if I do not have some Gigabit structure LAN here (and I don't), then CSA is USELESS to me? Are you saying that a NON CSA mobo with the LAN running, enabled, and ONLINE on a typical DSL connection is NOT going to be any slower that with it disabled? Are you also saying that the non CSA/PCI NIC "bandwidth sucking and hogging" will only come into play if one is on a gigabit network? My LAN here is just through BellSouth aDSL (1500k/256k) and my PC's are n'worked on a typical Ethernet router (DI-704 Dlink) 10/100.

Thanks.
 
When you're using that particular LAN connection for a DSL modem, you're going to run it at 10 Mbit - which could be done on ISA without choking.
You're going through a router, so you're on a 100 Mbit line up to the switch/router box. The 10 MByte/s throughput you'll get from that (20 on full duplex worst case) is still easily handled on PCI.

One last time: CSA is not some miracle technology that accelerates LAN connections. It is a dedicated datapath to a special Gbit LAN chip that has enough bandwidth to let the latter use its potential.
 
Yes yes yes....I know it's not miracle technology. 🙂 Thanks for the info Peter. This non CSA issue still does not come into play when using Southbridge RAID? On another thread someone seemed to mention that it would from what I could tell.
 
If the RAID is in the southbridge it does not use the PCI bus.

It will simply talk back and forth along the dedicated link between the 2 bridge chips (if need be). If you have a board with the CSA bus that dedicated path connects back up to the southbridge but that won't affect southbridge RAID in any appreciable way.

Look here:
http://www.anandtech.com/chipsets/showdoc.html?i=1823&p=3

Basically if you read that, and this page from the 875 review:
http://www.anandtech.com/chipsets/showdoc.html?i=1811&p=5
everything should be very clear on when and how CSA can either impact or increase performance of other subsystems such as Southbridge RAID, PCI RAID, PCI NIC, etc.

If you're talking about PCI RAID with heavy network usage then yes, that's one of the reasons why CSA was developed. It offloads network traffic from the PCI bus which may otherwise be saturated with a multidrive Promise or Highpoint IDE RAID setup.

Gaidin
 
Southbridge integrated RAID (as in VIA 8237 and Intel ICH5R southbridges, and NOWHERE else) runs on the chipset's proprietary, fast north-to-south connection. No bandwidth congestion there. All other onboard RAID solutions are PCI chips.
Of course, moving devices off PCI onto faster busses helps those devices that still are on PCI. So yes, if your mainboard has a PCI mass storage controller (card or onboard), then having LAN and other bandwidth intensive stuff off PCI is going to help.
 
I'm getting a mobo with ICH5R AND either 3112a or Promise SATAR so I can compare the ICH5R RAID performance to that of the other SATA RAID device. From what I've heard, the ICH5R is faster at SINGLE SATA drives, but not with SATA RAID. Can anyone vouch for that?

Thanks a bunch guys, great links too.
 
BTW, just what is considered heavy network usage anyway? Would this be just surfing the net & downloading/uploading on ADSL 1500k/256k shared between two PC's on a DLink DI-704 router? There is no file sharing involved, just the DSL connection. I'm trying to ascertain if I would ever need a CSA mobo in my configuration.
 
As I already said, all DSL/cable boxes run a 10 Mbit/s connection on the LAN port; maximum transfer rate on standard speed DSL is about 90 KByte/s, 1500k DSL gives twice that, around 180 KByte/s. Outbound you're at a rather measly 30 KByte/s.
That's not going to make even an ISA bus nervous, discussing the benefit of CSA over 32-bit/33 MHz PCI is absolutely pointless in that application - and using an expensive Gbit Ethernet chip for such a link is pearls before swine anyhow.
 
Those specs you're giving; if you mean the download and upload speeds, mine are much more than that. D'loads are about 500kb/sec, uploads are about 220kb/sec and thru-put is 1.6mb/sec. Would this still "leave me in the clear" IYO?
Thank you.
 
You're confusing kiloBITS with kiloBYTES. Your "double speed" DSL at 1500 kbits/s will give you a maximum of 180 KBytes/s download, and one sixth that upload. Even the measliest 10 Mbit/s ISA NIC potentially transfers slightly above 1 MByte/s each direction.
 
No, I mean the download speed in KiloBYTES per second. More accurately I should have said KB/sec instead of kb/sec. My specs I gave are for KiloBYTES per second......isn't that the format at which IE shows the download rates? KiloBYTES and not kilobits, right? Since it's always shown "KB" and not "kb" next to the download rate, I assume that is KiloBYTES/sec. When I download something (from a fast site) it will start at over 500KB/sec. Thru-put is 1.6 megaBITS/sec hence the correct "mb" in that case. My DSL is VERY "tweaked out". At any rate, will what I'm describing put a load on a NON CSA bus, or is this still a moot point, still not enough bandwidth?
Thanks.
 
Heh, you fell for that trap. IE, while you pick a filename for your download, already starts downloading the file. Once you finally hit OK, you get presented with an absolutely ridiculous transfer rate because the rate calculation started when you hit OK, but the actual data transfer started MUCH earlier.

With 8 bits making a byte, you cannot possibly transfer more than 1500 (1536 actually) Kbits/s which is 192 KBytes/s - minus the packet header overhead, this yields an actual throughput ceiling of about 178 KBytes/s. Basic rules of computing are always valid, even in Microsoft applications.

Get that, and please finally put the topic to rest. Everything has been laid out and explained.
 
FYI, I also get those speeds at sites that test d'loads/uploads & thru-put such as DSLreports, & many others, which are LESS accurate at actual download speeds than the download itself. And yes, I'm FULLY AWARE of Bits Vs. Bytes and the 8 divisor. My statement was questioning whether the shown IE d'load rate was BITS or BYTES.

Get that, and please finally put the topic to rest. Everything has been laid out and explained.
Click to expand...

Yeah........ I've got it. No one is forcing you or 'twisting your arm' to answer anything, or to participate in this thread! I've been polite and kind to you, saying "thanks or thank you" every time, and your attitude now is uncalled for. One never learns anything if you never ask questions.
 
Well, I didn't get impatient until I had to give you the same answer for the 4th time. I could have left earlier. I didn't. Who are you to complain?

Obviously you STILL believe in your PHYSICALLY IMPOSSIBLE transfer rate numbers. NOW I'm leaving this thread.
 
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