Are some gigabit LAN controllers unsuitable for ADSL use?

[Tomkovsky]

Hello. My first post - I have already found a lot of useful information on the website, but i have an unusual network problem which i can't figure out. Maybe someone can enlighten me.

I recently changed my home network from a dying wireless Belkin G based setup to a gigabit wired network (based around a new Billion 7800), thinking a wired network would be more solid. My ADSL service is currently a fixed rate 2Mb, which i want to regrade when i have sorted my network out. On the LAN, i have 4 PCs (3 desktop, 1 laptop) all with gigabit network controllers (all different makes). All cables are rated Cat5e. My problem concerns the download speeds i am experiencing on 3 out of 4 network computers - which are below even the wireless G network i had before. The only PC which downloads properly, has a Marvell 88E1111 controller on an NForce 4 (fairly old now) motherboard. This quickly tops out at around 250-260k/s when downloading files and is pretty stable. The other PCs have the following LAN controllers:

VITESSE VSC8201RX (MSI K8NGM2FID)
Broadcom 5787M (Laptop)
Netgear GA311 PCI Card

All of these controllers exhibit the same behaviour when initiating a file download: A delay of a couple of seconds, followed by a slow crawl up to a speed of just under 200kb/s, and very inconsistent speed between 150-200kb/s. Clearly this is not right for supposed gigabit controllers. I could understand a poorly performing controller transferring at below even 10mb/s, but not below 200kb/s.

I have tried swapping ports on the Billion to no avail, so i think its an issue with the network controllers. Is there any recommended setting either on the Billion adsl router or on the network controllers to stabilise internet file transfer speed? Are some gigabit controllers simply  unsuitable for the kind of data transfer which takes place on an ADSL line?

One thing i haven't explored is the file transfer performance between the PCs themselves. I have XP on all machines which doen't give any info on transfer speed when copying files. Any recommended (free) software to monitor LAN performance / file transfer speed?

If a regraded my ADSL to say an 8mb ADSL2 service, do you think the flakey connections would top out at the same speed or at a speed just below the proper transfer speed of an 8mb line? (ignoring ADSL attenuation, SN ratio etc..)

Thanks in advance to anyone who reads through my post without falling asleep and replies.

[kitz]

All should be fine for adsl.
Do you also have similar problems when transferring files between the network PCs?

After installing gigabit lan a few years ago... I found that some of the PCs were performing a bit slower than I expected, but it was still fine for adsl speeds.
Sorry I cant recall exactly what I changed ... but I did have a play with the advanced settings and things like jumbo frames, and all seems ok now.


For monitoring real time speeds try using Net Meter

[Weaver]

Rather belatedly I'll add my two pennyworth.

I have noticed a bad problem which sounds a bit like this myself this spring which are down to NIC and driver bugs or issues with ethernet flow control and switch-NIC compatibility.

There are a number of things that could be looked into here - a number of tests that could be done.

Because you are using WinXp boxes (not Vista or Win7) and are talking about internet traffic not over-LAN filesystem traffic, you don't satisfy the conditions to score a hit against a couple of 'diseases' that I've seen.

Did you find out any more about this ?

[BritBrat]

I have no clue what this is so take it with a pinch of salt.

But recently been reading about lan speeds and something croped up about "jumbo frames" or something like that that made it faster but your cards have to support it.

http://en.wikipedia.org/wiki/Jumbo_frame

Ooops, sorry I see Kitz already mentioned them.

[toulouse]

Forgive me for poking my nose in here, but......

Isn't the problem, if indeed there is a problem, likely to be the OPs 2Mbps DSL connection ?

[BritBrat]

Should be OK:

•Dual-WAN approach - ADSL2+ or Ethernet WAN for Broadband Connectivity
•4-port Gigabit Switch

Billion 7800

If he was talking about LAN speeds.

But will he ever see these recent posts !!