iMac G4 flat panel slow ethernet?

[JD2]

Hi there,

As supposed "Mac expert' I am frequently asked to look in to problems my less tech savvy friends have with their mac's.

This time I am a bit at a loss...
This is about an iMac flatpanel G4 that was connected wirelessly to a DSL modem router before. It al went well until wireless became very popular in the appartementblock were it was used. Since it was not possible to run a wired ethernet connection, I looked for a solution.

At the same time the DSL line was upgraded to VDSL2 with a 30Mbit down profile. As the wireless condition became worse and worse I suggested using
Devolo homeplugs (500mbit type) in the assumption this would rival an wired connection.

To my surprise the speed seems to be 'capped' to about 8Mbit/s with every single test. One might expect some gain as opposed to the 54Mbit/s (theoretically of course) wireless in less than ideal conditions before, no?

I checked the ethernet speed settings on the iMac and they are 100Mbit/s (highest possible speed on this machine I think)

Did anyone here have similar experiences, anyone found a solution?
Any suggestion is welcome...

 

[chibiterasu]

This sounds like you are referring to you Internet connection speed which is dictated by your ISP, line etc

It doesn't matter if your router and switches are gigabit or 500mibt you will only see that speed when your are transferring files or other documents through your local network e.g iMac G4 to a nas or another pc/mac on the local area network providing everything is connected through Ethernet whether that be router, power line adaptor, switches.

I would suggest plugging the iMac directly in the router on ethernet and see what speed you get if there is no change then its probably something to do with the line or the router (but routers are normally fine)

Hope that helps

 

[JD2]

You are correct about the 30Mbit/s, on the other hand I know for sure that on these lines it must be possible to go above 8Mbit/s to at least 15Mbit/s as the 30Mbit/s is indeed on the modem as the downstream sync speed.
My own line is similar and I get better results with even 3 powerline adaptors on a much more complex electrical installation.
I 'd have to test again but I think I even tested your suggestion (running a direct ethernet cable) with no real gain and for sure I have tested as it was wirelessly and got to not far less then the 8Mbit...
This all leads me to suspect a problem with the iMac and its ethernet connection (maybe even a soft bug???)
I could always try to take the airport card out of the iMac but then I have to open it up again for a long shot...

 

[chibiterasu]

Well all I can say is I've been with ISP's who have capped my speed even though the line is can take a faster connection and everyone's line is different.

I wouldn't say it is the iMac mine runs just fine on Ethernet even with a airport extreme card in it, I've never had to go into the settings of Ethernet, it just works. But is there another machine you can take round there and use, if its the same result then you know it's something to do with the line/ISP etc, if not then you know it's the iMac.

 

[alexrmc92]

You are correct about the 30Mbit/s, on the other hand I know for sure that on these lines it must be possible to go above 8Mbit/s to at least 15Mbit/s as the 30Mbit/s is indeed on the modem as the downstream sync speed.
My own line is similar and I get better results with even 3 powerline adaptors on a much more complex electrical installation.
I 'd have to test again but I think I even tested your suggestion (running a direct ethernet cable) with no real gain and for sure I have tested as it was wirelessly and got to not far less then the 8Mbit...
This all leads me to suspect a problem with the iMac and its ethernet connection (maybe even a soft bug???)
I could always try to take the airport card out of the iMac but then I have to open it up again for a long shot...

Have you tried bringing your friend's iMac to your location to see if you experience the same issues on another network. This all sounds like an ISP problem to me, especially with DSL type connections. I have seen DSL lines differ quite substantially.

 

[WMD]

Go into the Ethernet properties and see if you can find the MTU option (they've moved it around a bit over the years). It should be set to either 1500 or 1492. Other settings could cause slowdowns.

It would also be good to test a different computer on his network, and/or his computer on a different network.

 

[CubeHacker]

Do you get faster speeds on another computer plugged into Ethernet through these power line adapters? From what I understand, they promise fast speeds, but they rarely deliver.

 

[JD2]

Mtu

Go into the Ethernet properties and see if you can find the MTU option (they've moved it around a bit over the years). It should be set to either 1500 or 1492. Other settings could cause slowdowns.

It would also be good to test a different computer on his network, and/or his computer on a different network.

If I remember correctly it was set to 1500 so it should be ok but thanks for the tip, I will double-check.

----------

Do you get faster speeds on another computer plugged into Ethernet through these power line adapters? From what I understand, they promise fast speeds, but they rarely deliver.

In my personal case they do deliver, I also have 500Mbit types.
They even do the job in 3 phase connections, like mine are.
Even tree in my case but it could be they do not work as good in old wiring.
Having 'clean' power does also help I presume.

And then again, 500Mbit/s is far beyond the 8Mbit/s I get.
But it is also possible that they are the culprit, will try with another machine on the same connection to exclude the connection side as cause.

Thanks for replying!