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I have a USB 2.0 External HDD and when I transfer something to/from the HDD over a gigabit network, I have a 120MB transfer speed, but USB 2.0 over supports 35MB

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the Operating systems often cache data in the RAM before writing them to the Disk. This may cause that you thing the write speed is high. – magicandre1981 Nov 12 '13 at 5:07
Likely whats happening is the transfer rate you are reading isn't actually what is being transferred, rather, it is the maximum that can be transferred at all. Your drive cant support 120MB/s, so it only transfers 35MB/s, but if the device COULD transfer 120M/s, it would. Its like how my computer can have a 100MB/s Internet connection, but my modem only supports 25MB/s, so I only get 25MB/s. – Ben Franchuk Nov 12 '13 at 5:18
no @BenFranchuk if it says its transferring at 120MB it's actually doing so. I agree with magicandre1981 . caching until it can write to disk – PsychoData Nov 12 '13 at 5:20
@PsychoData The cache is not infinite, so Joe just needs to do a longer transfer to see if the performance drops. – Paul Nov 12 '13 at 5:48
@Joe: Out of curiosity, where are you seeing this performance? You mention transferring something over a Gigabit network, but then talk about USB 2.0's limit of 35mb/s. I'm a bit confused about the exact chain of events...where does the Gigabit network come into play? – jrista Nov 12 '13 at 5:49

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