Internet Download Performance

Robert's Avatar


23 Jan, 2021 11:46 PM

I am using TenFourFox release 23 on a PPC Mac G5 connected via it's 10/100/1000Base-T-E Ethernet port.

How come for my Comcast internet service (275 Mbps download service) I am only measuring using TenFourFox approximately 95 Mbps download.

On the same network, connected through the same router on my iMac, Firefox, I get 275 Mbps download.


  1. Support Staff 1 Posted by Cameron Kaiser on 24 Jan, 2021 12:17 AM

    Cameron Kaiser's Avatar

    And what do other browsers on your G5 get?

  2. 2 Posted by Earthlink on 24 Jan, 2021 12:20 AM

    Earthlink's Avatar

    Good question, they do not even work with Comcast Internet Speed Test.

  3. Support Staff 3 Posted by Cameron Kaiser on 24 Jan, 2021 01:38 AM

    Cameron Kaiser's Avatar

    Without knowing the details of the test, but guessing from other such speed tests, the test may be at least partially dependent on the speed of the machine running it to keep pushing data.

    For the record, I only wish I got 95Mbps at my house.

  4. 4 Posted by Earthlink on 24 Jan, 2021 01:44 AM

    Earthlink's Avatar

    > On Jan 23, 2021, at 5:38 PM, Cameron Kaiser <[email blocked]> wrote:

    It could be the Mac G5, it is old, but the Ethernet port is highly spec’ed.


  5. Support Staff 5 Posted by Chris (chtrusch... on 24 Jan, 2021 09:45 AM

    Chris (chtrusch)'s Avatar

    I see a similar effect. The 'official' test of the German Federal Network Agency (which we can use to complain if we don't get the speed we pay for) says I get a download speed of 215 Mbit/s when I use Waterfox on my MacBook Pro running 10.11. This is the correct speed. It measures only 15 Mbit/s with TenFourFox and Leopard Webkit on my G4 PowerBook running 10.5. All tests with gigabit ethernet connections. When I use WiFi on the PowerBook it's considerably better and probably only limited by the speed 802.11g can do on my network.

  6. Support Staff 6 Posted by Cameron Kaiser on 24 Jan, 2021 04:33 PM

    Cameron Kaiser's Avatar

    I really do think this is a CPU limitation.

  7. Support Staff 7 Posted by Chris (chtrusch... on 24 Jan, 2021 05:31 PM

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    The weird thing is that the ethernet port on the PowerBook is *a lot* faster (at least one order of magnitude) when I push files around on my intranet.

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