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Ethernet connection between two Power Macs is very slow

Discussion in 'PowerPC Macs' started by jowie, May 7, 2011.

  1. macrumors 6502a

    I'm currently trying to port all my old stuff from an old Power Mac G4 (MDD) to a newer Power Mac G5 (Late 2005). Both have gigabit ethernet and so I decided to connect the two via ethernet cable (Cat6). Both are running OS X 10.5.8.

    However... I'm only getting speeds of up to about 40Mbit/s, and it's taking hours (nearly a whole day in total) to transfer about 200GB. Are there any reasons why it might be so slow, and is there any way I can speed it up?


  2. macrumors 65816


    Are these macs connected to the internet via airport? Is so, turn airport off, maybe that will help.
  3. macrumors 6502a

    Thanks for that idea... The older G4 had its AirPort turned on, whereas the G5 doesn't yet have a wireless card. I just turned the G4 AirPort off and it went up slightly (up to about 45Mb/s), but has settled down again to just under 40...

    It's weird, I can transfer files on .11n faster than this! :p
  4. macrumors 65816


    Is there any other Ethernet ports on either of the powermacs? Try using different ports.
    If there isnt more than 1 port, try a different cable, maybe there's and issue with it?
    Maybe completely remove the airport card on the g4?
    Try quitting any other apps running in the background?

    This is a weird issue! I don't see why you won't get full speed....
    Hope it helps!
  5. macrumors 68020


    Check in network preferences to be sure your ethernet on both machines is set to gigabit. Sometimes it isn't set to GB automatically even when both ends are.
  6. macrumors 6502a

    Hi sorry, should've checked back here earlier...

    I checked the Network prefs, and both Ethernet connections were set up as Gbit, so I guess it's not that... It could be the cable, but I didn't get round to trying to remove the AirPort card (although I'm a bit dubious as to whether that would have worked)...

    Anyway luckily the transfer has *finally* finished :) but I will keep an eye on it, just in case I need to do any more transfers. Thanks for your suggestions!

  7. macrumors 65816


    Not a problem!
  8. macrumors 6502a

    Hi, me again!

    I think there might be a problem with the Ethernet ports on the G5. Last night I wanted to do a Time Machine backup from scratch, so I plugged the Time Capsule directly into it using a cat6 cable (think it was a different one this time but can't be sure) and left it backing up overnight (about 150GB). I watched the start of the transfer and it was reaching about 75Mb/s.

    This morning I went into the room to find that it had only backed up about 30GB in about 8 hours, which is pretty awful. I checked the Ethernet settings again and they are set to Automatic (but showing "1000baseT" when connected). I don't think it's a problem with the speed of either of the hard drives, because the Time Capsule has no problems when connected to another machine (it's still slow to backup but not THAT slow), and I tested the speed of the internal drive by duplicating a 50GB folder which took about 25 minutes.

    If there are any other good tests to do then please let me know. Luckily I won't really need ethernet once the backup has entirely finished, I also have a .11n wireless card on order and to be honest it should be faster than the ethernet speeds I've been getting anyway!

  9. macrumors 65816


    It could be that cable!
    Also, are there any programs running in the background during the transfer?
  10. macrumors 6502a

    I've used three different cables now, two cat6 and one cat5e - all about the same speed. No programs running in the background. I've checked Activity Monitor and everything looks pretty normal.

    Could it just be that I'm expecting too much for the protocol? Maybe 40Mb/s is about right for a network file transfer between hard drives... What do you think?
  11. macrumors 65816


    It could be bottlenecked at the speed of the hard drives........ Though I think you should get somewhat faster speeds.
  12. macrumors 68020


    You would have to be using a hard drive from the late 90's for it not to be able to keep up with gigabit ethernet. Any modern drive (even at the extreme low end) can easily keep up and have transfer speed to spare.
  13. macrumors 68030

    40Mb/s is only 5MB/s, the hard drives in the G4 MDD should easily do 40MB/s, even when it's pretty filled.

    Gigabit ethernet is good for about 105MB/s, so that's definitely not the bottleneck.

    I recommend assigning new IPs to both machines for the gigabit interface and connect them via cmd+k specifically using that IP address. That way, you're definitely not going any other route using WLAN or something like that.
  14. macrumors 6502a

    Throw a firewire cable between the two and call it a day if you can't figure out the ethernet issue.

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