How efficient should a decent gigabit net be?? I am missing something, I'm afraid, as I only get about 64 mb/sec, or around 6-8% effiency, unless I missed a power of ten somewhere I used the PASSMARK network test and got these figures for 2 machines [cat 6 cable, cpu usage approx 35% for each] over 30 seconds. I have 2 intel pro/mt1000's, through a trendware gigabit switch on a network with only these on it. I have offloaded all calculations/checks as possible, and tried jumbo frames. It doesn't seem that about 7% efficiency is correct. any ideas what I'm doing wrong, or a better way of checking?? It certainly seems a lot faster, but I must be screwing up my math somewhere

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This is out of head math, don't count on it to be accurate, but gigabit should let through about 120 MB/s...

People often confuse bit and byte bandwidths... There are 8 bits in 1 byte, as you most certainly already know... So, 1kilobit net, would pass only 125 bytes... OK, to recalculate those bandwidths now...

1 Gb => 1,000 Mb => 1,000,000 Kb => 125,000 KB => 122.07 MB

unless I'm doing my math wrong too... You divide bits with 8, to get bytes, and you know how to get kilo-, mega-, and giga- bytes from bytes, multiplying them with 1024...

I hope this helped a little... But as I said, don't take it for sure, it's out of head, and a quickie...

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The above is almost right.

10 Mbit/s = 1,25 MB /s = 1 280 KB/s
100 Mbit/s = 12,5 MB/s = 12 800 KB/s
1000 Mbit/s = 125 MB/s = 128 000 KB/s

Those speed are linerate there are you (loose) some speed with :
- IP headers and others overhead like checksums , ....
- Windows that reserves some bandwith on the connection for internet and so.

So I should say that your connection works fine.

Check the length of your cable there is a minimum distance of the cable.
For Cat 6 this minimum length is longer then for Cat5.
For Gigabit is cat 5 (or Cat 5e) mostly enough.

And if you use your connection to copy some data between 2 PC's there is also the limition of the hard drive.
To solve this you have to use a RAID array with several drives.

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I would say everything depends on the use of that. Nowadays streaming video as communication can fully load even a gigabit channel, so it makes a lot of sense to start using it in places it fits.

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The efficiency of gigabit depends on mainly the CPU power of your computer as well as which gigabit chipset you are using. Some dual gigabit models use a chip from realtek, which is not very well performing as far as efficiecny is concerned, as the bandwidth will have to go to the southbridge before being usable. Also, if you are using PCI-E card, there will be bottleneck at the PCI-E interface. So the best chip I think should be nforce's gigabit and it can which more then 80MB.

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