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View Full Version : G74SX USB 3.pe0 Transfer Speeds...Wheres my speed, bro?!



hirethestache
10-23-2012, 10:35 AM
I have scoured the web for an answer, but I am not anywhere near an expert in this field to know when I'm looking at a solution or not. Using a variety of external drives, I have yet to achieve a USB 3.0 transfer speed of more than 80mb/s--this is welllll below the theoretical limit of 500mb/s. Moreover, my average speed caps off at 45mb/s.

What are your speeds, and which drivers are you on?

cl-scott
10-23-2012, 04:32 PM
First off, the important word there is "theoretical", and then it needs to be mentioned that those are BURST speeds not SUSTAINED speeds. Beyond that, there probably needs to be a discussion about the difference between megaBITS per second, which is what USB speeds are measured in, and megaBYTES per second which is what file transfers are measured in. The quick and easy way of estimating is to just divide megabits by 10 to get megabytes. Moving on from there, you also have the problem of overhead. If you're trying to transfer 1,000 files that are all say 1MB each, it's going to be much slower than transferring a single file that is 1,000MB.

All of those things can combine in an almost infinite number of ways to kind of confuse the issue. So asking people what they might be getting doesn't really do you any good, because they aren't necessarily apples to apples comparisons. Someone transferring that single 1,000MB file will likely have much better overall speeds compared to someone moving 1,000x1MB files, and all manner of other things. I didn't even get into how programs like an AV scanner could impact speeds, or that USB relies on the host CPU to do a lot of the heavy lifting so if you were doing video encoding at the time, it might impact transfer rates. Moving files from a platter based HDD to/from flash drive will be different from SSD to/from flash drive, etc.

You're trying to look at a single metric in isolation, when that particular metric is influenced by a significant number of other factors.