Fake ethernet cables, Time Capsule drive speed

Discussion in 'Mac OS X Server, Xserve, and Networking' started by Undecided, Jul 21, 2016.

  1. Undecided macrumors 6502a

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    California
    #1
    I just discovered that the Cat 5E cable I bought off eBay is not actually Cat 5E. It's labeled Cat 5E, but I can only get 90 mbps through it. Damn. I hate getting ripped off.

    Swapping out the cable with a known Cat 5E one immediately increased my transfer speed to over 300 mbps. I was copying a blank disk image to a Time Capsule. I'm deducing, then, that the drive in the Time Capsule (5th gen) is a USB 2.0 connection (the inside drive), with 480 mbps providing actual throughput of 300+.

    Which is all frustrating. I have a newfound desire for speed. I want my gigabit network to operate at gigabit. I should be getting transfers close to 1000 mbps, given the little overhead of wired ethernet.

    And which brings me to Thunderbolt. I hate that it's more expensive than USB 3, but I do want speed.

    So, no question in this post, but I thought I'd alert people to the fake ethernet cables out there. Searching through the web just now, it seems this is pretty common.
     
  2. Altemose macrumors G3

    Altemose

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    Elkton, Maryland
    #2
    Actually, Cat 5 in short strands can actually pull over 100 Mbps. It is likely that your "Cat 5E" cable has a bad crimp on one end, as Gigabit requires more pairs than 100 Mbps.
     
  3. IHelpId10t5 macrumors 6502

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    Nov 28, 2014
    #3
    I just have to ask. Why, why, why would you buy something as inexpensive as an ethernet cable on eBay? You can buy a 6ft. quality, name-brand (Belkin, etc...) Cat5e cable for like $5 directly from the manufacturer so why eBay?
     
  4. Undecided, Jul 25, 2016
    Last edited: Jul 25, 2016

    Undecided thread starter macrumors 6502a

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    #4
    Interesting. I'm not sure how I could check for that though so I think I'm just going to bin it, or use it with a 100mbps device, like a net cam. Edit: wait, by crimp, do you mean a bend along the cable, or bad RJ45 attachment?

    --- Post Merged, Jul 25, 2016 ---
    Well, it was 50' but, anyway, just 'cause i got drawn into the 'buy it online' frenzy.
     
  5. Altemose macrumors G3

    Altemose

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    #5
    Either; but I was referring to the RJ-45 attachment. If there is any break in the wires across the whole cable it can knock it back from Gigabit, and if there is a bad RJ-45 connection where one or more of the teeth are not getting a good bite in the cable it will not pull Gigabit. Personally, I would just get a box of 250 feet of Cat 5e, a quality crimper, and a bunch of RJ-45 connectors (from a known company not the cheap ones) and simply make your own cut to fit.
     
  6. typonaut macrumors member

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    May 7, 2014
    #6
    You can use a dedicated ethernet cable tester, or you can test for continuity (or resistance) on individual cable strands with a standard test meter.
    --- Post Merged, Jul 26, 2016 ---
    Personally, having had experience of doing this, I couldn't be bothered making up my own cable lengths - unless I was doing particularly long stretches (ie 5 metres or more). The time it takes is just not worth the hassle, particularly on short cables.
     
  7. kohlson macrumors 6502a

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    #7
    I have a 4th gen TC, and have swapped out the original drive for a 4TB. It's a standard SATA-3 (6Gbps).
     
  8. Undecided, Jul 26, 2016
    Last edited: Jul 27, 2016

    Undecided thread starter macrumors 6502a

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    #8
    The drive may be SATA III but what is the connection to the drive? On BlackMagic, I get about 33 Mbytes/sec. What do you get?
     
  9. Altemose macrumors G3

    Altemose

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    #9
    Once you crimp cables as much as I do, it becomes a quite speedy process.

    A Time Capsule is going to average around 30-35 MB/s, and a USB connected drive will get around 22-27 MB/s.
     
  10. Undecided thread starter macrumors 6502a

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    #10
    What should you expect from a good NAS, over gigabit ethernet?
     
  11. monokakata macrumors 68000

    monokakata

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    #11
    I ran BlackMagic on my Synology DNS 412+ via gigabit ethernet, and saw some 100+ peaks for both read and write, but eventually it settled down in the mid-80s.

    The volume I tested is a pair of 4 TB 7200 rpm disks in Synology Hybrid RAID (mirroring).
     
  12. Altemose macrumors G3

    Altemose

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    #12
    With 7200 RPM hard drives you will probably see around 80 MB/s on a solid NAS.
     
  13. IHelpId10t5 macrumors 6502

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    #13
    As someone that has crimped many UTP cable lengths over the years I can provide some additional insight. I agree completely that you should not build "shorter" custom Cat 5e cables where they can be otherwise purchased from a reputable manufacturer like Belkin (e.g. less than ~50'). However, for unusually long Ethernet cables that need crimped RJ45 ends (i.e. non punch-block termination) crimping can be done quite effectively if you use quality cable, quality jack ends, and a crimper that matches. The reason that purchasing manufactured cables is a better, is that they use multi-stranded copper that is far more flexible, and they crimp, mold, and test the resulting cable consistently. When you build you own cables, you will likely use UTP cable with solid 24AWG wires. Even if you get this right in the initial crimping, I have found that over many years, these crimp ends can loosen and become less reliable than factory manufactured cables.
     
  14. KillaMac Suspended

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    May 25, 2013
    #14
    Use monoprice.com if you want to get reasonable cables.
     
  15. VideoFreek macrumors 6502

    VideoFreek

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    #15
  16. Mikael H macrumors 6502

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    #16
    Just a short question: Why buy CAT5e at all today? Gb ethernet is close to the limits of that standard, while CAT6 is entirely comfortable with it. And as others have written: buy from reputable sources or terminate your cables yourself. You can't possibly save enough money to motivate the headache of troubleshooting dodgy cables.
     
  17. KillaMac Suspended

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  18. satcomer macrumors 603

    satcomer

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    #18
    Plus to everyone make sure when you get CAT 6 cable that you also use Gigabit switches!
     

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