The MASM Forum

Miscellaneous => The Orphanage => Topic started by: Magnum on November 17, 2014, 03:59:55 PM

Title: Confused about transfer rates of USB 2.0
Post by: Magnum on November 17, 2014, 03:59:55 PM
USB 2.0 was released in April 2000 (now called "Hi-Speed"), adding higher maximum signaling rate of 480 Mbit/s (due to bus access constraints the effective throughput is limited to 35 MB/s or 280 Mbit/s

I am getting 2 Mb/second copying files from my laptop to an external Toshiba hard drive. ??

That's seems awful slow.

Is it ?

I know megabytes are different from megabits.



Title: Re: Confused about transfer rates of USB 2.0
Post by: Magnum on November 18, 2014, 10:45:32 AM
After installing a USB 3.0 board, I am getting 40 Mb/sec transfer rate.

Did not expect that great an increase over 2.0.
Title: Re: Confused about transfer rates of USB 2.0
Post by: SoraK05 on November 19, 2014, 11:28:19 PM
USB 3.0 can go above 100MB/s.
USB 2.0 is common for things like backup loaders on some consoles, and in general should read/write around 20MB/s depending on the drive.

USB Flash Drives or TransFlash memory may vary in their ability. USB 2.0 should be able to get around 30MB/s in something as direct as linux.

A portable hard drive drive should manage at the ~20MB/s.
Your install or hardware may be damaged. It appears your speed is very slow where it shouldn't be.

Sometimes you can plug in a hard drive and a message comes up that it is not in USB 2.0 mode, and you can try unplug/replug or another usb port if you used the front port on a desktop for example.

Perhaps the unit your hard drive is in may be damaged, and you can try removing the hard drive from the enclosure and using another enclosure/generic enclosure.

You can also try an enclosure using 2 usb ports for additional power if the hard drive is larger in size and doesn't use mains.
Title: Re: Confused about transfer rates of USB 2.0
Post by: Magnum on November 23, 2014, 02:33:18 AM
Quote from: SoraK05 on November 19, 2014, 11:28:19 PM
USB 3.0 can go above 100MB/s.
USB 2.0 is common for things like backup loaders on some consoles, and in general should read/write around 20MB/s depending on the drive.

USB Flash Drives or TransFlash memory may vary in their ability. USB 2.0 should be able to get around 30MB/s in something as direct as linux.

A portable hard drive drive should manage at the ~20MB/s.
Your install or hardware may be damaged. It appears your speed is very slow where it shouldn't be.

Sometimes you can plug in a hard drive and a message comes up that it is not in USB 2.0 mode, and you can try unplug/replug or another usb port if you used the front port on a desktop for example.

I am getting 40Mbps. Why do say my speed is slow ?
Title: Re: Confused about transfer rates of USB 2.0
Post by: SoraK05 on November 23, 2014, 05:08:30 AM
40Mbps sounds like a high. However, this is on the USB 3.0 Board.
The question referred to a possibly faulty USB 2.0 Board in the first post giving only 2MB/s which is unusual.