Thunderbolt to Ethernet into Macbook Pro more than halves my internet speed?

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I have a late 2014 MBP i7 15inch 2.2ghz (3.4ghz) and I have been happily using wireless to work, recently I have begun streaming and I wanted a more stable connection so I bought the gigabit to thunderbolt ethernet adapter so i could wire up my connection.

I have now gone from 160 mb/s to 40 mb/s and I cannot figure out why this has made me so much slower? I used to wire up my old MBP which had the ethernet port and that was a stable 160 mb/s but this adapter has quartered the speed of my connection on this newer model.

Do I have a setting wrong or is this a known problem with the adapter?
 

bobtomay

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First off, we have no idea how/what you're actually testing nor comparing.

If you're testing your internet download speed, what download speed are you paying for?

Try a different ethernet cable. I once spent a month trouble shooting a network issue, including buying a new NIC, returned it as defective and got another to finally figure out it was the cable.
 
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First off, we have no idea how/what you're actually testing nor comparing.

If you're testing your internet download speed, what download speed are you paying for?

Try a different ethernet cable. I once spent a month trouble shooting a network issue, including buying a new NIC, returned it as defective and got another to finally figure out it was the cable.

Hi thanks for your answer, I am using speediest.net as my speed comparison, i pay for 160 mb/s and its what i usually get wirelessly or wired (on my PC and old macbook). Tried two different cables both the same result, 160 mb/s wireless, 30-40 mb/s when using thunderbolt.
 

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Testing must be at same time on both - not 30 minutes, an hour or day apart.

If you're geting those results with back to back testing, then I'd take the adapter in to your nearest Apple store to let them test/replace &/or return it.

edit:
And just as an FYI: Don't see that ethernet is going to be any more stable. With a 40 Mbps internet connection, I regularly stream HD movies in 2 directions via wifi without issue - from the internet to my computer and simultaneoulsy via Airplay to an AppleTV - that's using Netflix, Amazon, Vudu, iTunes, MGo, HBO Go, and several others.

(Well, actually iTunes wouldn't be in the above group, as I would only be streaming it in a single direction.)
 
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Testing must be at same time on both - not 30 minutes, an hour or day apart.

If you're geting those results with back to back testing, then I'd take the adapter in to your nearest Apple store to let them test/replace &/or return it.

edit:
And just as an FYI: Don't see that ethernet is going to be any more stable. With a 40 Mbps internet connection, I regularly stream HD movies in 2 directions via wifi without issue - from the internet to my computer and simultaneoulsy via Airplay to an AppleTV - that's using Netflix, Amazon, Vudu, iTunes, MGo, HBO Go, and several others.

(Well, actually iTunes wouldn't be in the above group, as I would only be streaming it in a single direction.)

Hi i meant I am streaming OUT, i.e. streaming content to Twitch, I have noticed an upgrade in quality of streaming out since i wired up. I have never had an issue wireless at home streaming or streaming in i.e. from Netflix, but streaming out I have noticed more quality.
 

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As far as I am aware, there is no ISP in the world that's providing individual users anywhere near the speed you are claiming - particularly for upload speeds. I'd be interested to know what service you have and see a screenshot of a speedtest.
 
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As far as I am aware, there is no ISP in the world that's providing individual users anywhere near the speed you are claiming - particularly for upload speeds. I'd be interested to know what service you have and see a screenshot of a speedtest.

Hi mate afraid to tell you its true! I am surprised you are saying this especially in Texas where I know Time Warner cable provides 300 mb/s down and 12 mb/s up? (a friend who streams to Twitch in Austin screen printed his speedtest to prove it?

I am with virgin media in the UK and i consistently get 156 mb/s down and 11 mb/s up.

here is a link to my recent test

Speedtest.net by Ookla - My Results
 
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As far as I am aware, there is no ISP in the world that's providing individual users anywhere near the speed you are claiming - particularly for upload speeds. I'd be interested to know what service you have and see a screenshot of a speedtest.


Also please remember America is not the world!! In South Korea up speeds of 20-30 mb/s are quite standard for their services, we are slow in comparison to them. Although I have heard 20 mb/s up are coming to the UK within this year as well as 200 mb/s down which I will be upgrading to when available.
 

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In both of your first 2 posts, you were complaining about problems with 160 Mbps being slowed down to 40 Mbps.

I made that comment based on your response in post # 5 where you stated you were talking about upload speeds, not download speeds.

Hi, I meant streaming OUT, i.e. streaming content to Twitch

So, I am now confused since you don't have those speeds for upload.
 
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In both of your first 2 posts, you were complaining about problems with 160 Mbps being slowed down to 40 Mbps.

I made that comment based on your response in post # 5 where you stated you were talking about upload speeds, not download speeds.



So, I am now confused since you don't have those speeds for upload.

ok super simple.....

wireless: 160mb/s down 11mb/s up.

Wired through thunderbolt adapter: 30/40mb/s down 10mb/s up

how can I fix this as I would of assumed wired would be better?
 

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I don't have an answer other than the one above...

...

If you're getting those results with back to back testing, then I'd take the adapter in to your nearest Apple store to let them test/replace &/or return it.

...
 

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Hi mate afraid to tell you its true! I am surprised you are saying this especially in Texas where I know Time Warner cable provides 300 mb/s down and 12 mb/s up? (a friend who streams to Twitch in Austin screen printed his speedtest to prove it?

Your friend neglected to tell you those speeds were before Time Warner starts to throttle them. Kind of wonder what he gets after he's been on line for awhile? ;D
 
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I have now gone from 160 mb/s to 40 mb/s and I cannot figure out why this has made me so much slower? I used to wire up my old MBP which had the ethernet port and that was a stable 160 mb/s but this adapter has quartered the speed of my connection on this newer model.

This is a very interesting thread for me.

So many places that things can go wrong, the quality of the copper as bobtomay said is probably the first place I'd be waving a disapproving finger, however, it could also be the ASIC in your switch/router, we received a batch of Cisco switches with faulty ASICs which caused the craziest list of problems. Now you're probably using the Virgin Media router (huge assumption on my part) which should not have the ASIC quality of a Cisco switch, but even so, 40Mbps would be pretty shocking and I'd be surprised if the most basic of QA checks let that one through.

Anyway, lets look at testing the actual communication in your home, do you have another computer inside the house that has the ability to use both wireless & wired?

This second computer does not need to be a Mac.

You want to install something called iperf iperf or iperf3 and install it on both machines.

This is a super simple application that will dump a bunch of UDP or TCP packets into your network, you use one device as a server and one device as a client, this thing will burst enough data for you to see what throughput you achieve.

I would try a bunch of tests if I were you, so wired-to-wired, wireless-to-wireless, wired-to-wireless, etc etc etc (also, if available, repeat the tests with different copper, you might be surprised at how big a difference this cable can make).

This will give you a real idea of what the hardware can deliver. The least productive test will be the wireless-to-wireless as your wireless AP (presumably the Virgin modem) will be the bottleneck as the way wireless works means that the device will struggle to give both clients perfect throughput at the same time.

The commands for iperf are super simple

Code:
iperf -s  
iperf -c ip.address.of.first.computer

Why is there a difference between wired & wireless? It may be the thunderbolt adapter, but it may be the VM Router, it may prioritise the wireless traffic in which case I would expect the wired-to-wired tests to see the same limitations.

I'm not offering any hard and fast answers here, just a little more troubleshooting to help you pin down the cause of the problem.

Some really simple OS X instructions for iperf testing: Test your home network and much more detailed instructions on the iperf command set can be found here: clicky.
 

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