How fast should an external drive be?
Please see the below table to compare the maximum performance of each interface.
External drive Internal drive
USB 1.1 Up to 12 Mbits/sec UltraATA 100 Up to 100 Mbytes/sec
USB 2.0 Up to 480 Mbits/sec Serial ATA 1.5 Up to 1.5 Gbits/sec
USB 3.0 Up to 4.8 Gbits/sec SATA 3.0 Up to 3.0 Gbits/sec
SATA 6.0 Up to 6.0 Gbits/sec
1394a (Firewire 400) Up to 400 Mbits/sec
Up to 1.5, 3.0, 6.0, or 1394b (Firewire 800) Up to 800 Mbits/sec Serial-Attached SCSI (SAS) 12.0 Gbits/sec
eSATA Up to 1.5 or 3.0 Gbits/sec
Thunderbolt Up to 10 Gbits/sec
Please note carefully not only the numbers, but also the units of measurement.
This table shows how much maximum total bandwidth is available per bus for each technology. Advertised transfer rates are based on the fastest speed at which the drive can send data back and forth across the cable (or bus) from the drive buffer.
Data transfer will go as fast as the slowest device or bus As technology progresses and newer, faster interfaces are developed, a user can have a collection of devices of varying interfaces, whose top speeds can vary widely. The computer will move data during a given transfer as quickly as it can, taking into account the abilities of all the devices involved in the transfer:
the source disk the interface over which the data is moving the destination disk
It may be that the source disk is newer and can push data faster than the destination disk can write it. Example: Backing up the data contained on a Serial ATA 6.0 drive to an external drive equipped with a USB 2.0 interface. The Serial ATA drive and interface are faster than USB 2.0, so the USB 2.0 drive and interface are the "bottleneck".
It may be that the destination disk and the interface can move and write data faster than the source disk can send it. Example: Backing up the data contained on a Serial ATA 3.0 drive to an external drive equipped with a Thunderbolt interface. The Thunderbolt interface is faster than SATA 3.0, so the SATA 3.0 drive and interface are the "bottleneck".
Burst transfer rate vs. Sustained transfer rate Many hard drive users mistake the "burst transfer rate" in the table above for what they can expect to see in real-world performance. This leads almost invariably to disappointment when their USB external hard drive does not transfer data at 50 MB/sec or their SATA internal drive at 300 MB/sec. This is because no storage device will have all of this "potential" bandwidth available for data transfers. Some of the bandwidth will be shared with other devices on the bus and some will be consumed by commands and interface protocol overhead. Other limitations can include the transfer rate that is possible given the bus (ie, USB, SATA, Thunderbolt). It is also worth noting that poor or slow drive performance is usually caused by a system configuration factor. It is very rare that poor performance is directly related to the drive. In many cases, perceived poor drive performance is usually attributed to the results of a benchmark test. Benchmark results are very system-dependent and the results can vary from system to system. For this reason, Seagate cannot provide a single sustained transfer rate specification for any drive.
Other Tips for Increasing Performance
Try connecting USB external drives into the various USB ports on your computer and experiment with data transfers via each port. It may be that some of the ports on the computer use older USB hardware. For best performance, do not connect external drives to USB hubs, switches, or extension cables. Defragment the disk drive (not for use with solid state drives). The drive's partition can become fragmented in the course of normal usage. Running the defrag utility in Windows can often improve the performance of a slow drive by consolidating scattered files and data, making it easier to access more quickly. Run Seatools for Windows on the drive. Run checkdisk on the drive (not for use with solid state drives). Replace your USB cable with a known-good cable. Empty the recycle bin/trash can, especially if the drive has been used for a while. Old data removed from the drive leaves behind a footprint on the drive, which can negatively affect performance. Many computers have numerous programs running in the background that are occupying system resources. Shut down some or many of the background programs. Please consult Microsoft Support (for 8/7/Vista) (for XP) for directions on disabling background programs at computer startup. Please see this Microsoft Support article for directions on using the Windows Task Manager to end processes. Boot to Safe Mode and try a data transfer to see if that increases the performance. My drive occasionally gives a $Mft error.
Unfortunately, $Mft errors usually indicate a corrupted partition.
Please follow these steps:
1. Troubleshoot the partition. 1. Backup the data on the drive (if it is not already backed up). 2. If this is not possible, use File Recovery for Windows to recover the data (if necessary). 3. Once complete, or if the data was already backed up, use "chkdsk /f" to try to repair the partition. Also see Document ID: 184611 for more information. 2. These errors are also sometimes seen in conjunction with delayed write failures. 3. Confirm that the external drive you have is supported in the operating system you have. For example, no external drives are supported in Windows 2000 Server, Windows 2003 Server, or Windows 2008 Server. A drive connected to a Server computer like this might indeed work for a while, even a great while. But often problems like the $Mft error occur. So, use the external drive on a different, supported operating system. See Document ID: 202393 - Seagate and Maxtor Compatibility Chart for Windows Vista and Document ID: 211931 - Will my drive work with Windows 7? 4. This error sometimes means that the drive itself is failing. Use Seatools for Windows or the drive's bundled diagnostic software to test it. Optional diagnostic software tutorials: o Seagate FreeAgent Pro o Seagate FreeAgent Go
Moving Data Between Two Systems Using an External Hard Drive (for MacOS)
In most cases you can use your external hard drive to copy data from one computer to another. It is recommended that you only copy data (i.e. pictures, documents, music, etc.) and not applications. Applications will not function when they are copied to a different system. Also, please note there may be a file system compatibility issue. Please see the "File system compatibility between operating systems" section below.
To copy the data to the external hard drive:
There are four main ways to save data (or "backup") to your external drive: manually (using the copy & paste or the drag & drop method), creating image/clone backups, using a backup software, and using backup programs included within Windows or MacOS.
To backup your data manually, please see Document ID: 206295 for instructions, Remember that you may always backup manually, whether or not you are also using a backup software. Many Seagate and Maxtor-brand drives include backup programs, and you may use these as well as manual methods to perform backups. To use a backup software, simply install the software that came with your drive and configure the backup to run when you launch it or on a scheduled basis. See our How To section for how-to videos and other resources to help you set up your backup program. See Document ID: 201413 for a list of programs by drive model. To use MacOS native backup systems like Time Machine, please check with their manufacturer documentation. Here are some examples: o Apple Time Machine 101 - Seagate Style o MacOS Time Machine
File system compatibility between operating systems
Windows OS to MacOS:
The GoFlex line of drives includes an NTFS driver, which can make NTFS file systems usable in MacOS. See Document ID: 219103 for more information. This is the best solution Seagate offers for transferring data between Windows and Mac computers.
You may also format your external drive into FAT32 for use between Windows and Mac computers. See Document ID: 200895 for instructions. It is only possible to read FAT and FAT32 formatted drives in a Macintosh with OS 10.2 or earlier. Using a FAT32 formatted drive within the Macintosh environment is only recommended for a short period of time to transfer data.
Data corruption will possibly occur when using FAT32 over an extended period of time in a Macintosh. Also keep in mind, that you will have a 4 GB file transfer limitation. Do not use NTFS formatted drives.
For non-GoFlex drives, Mac OS X 10.3 Panther or later works with local NTFS-formatted volumes, but the volume will be read-only. You will be able to copy data from, but not to, the external hard drive. With FAT32, it is recommended that the volume/partition size of the external hard drive not exceed 32 GB.
If you have an NTFS formatted disk, you must use another method to transfer the data from the Mac computer to the NTFS formatted external drive.
Please also see the following Apple article: How to transfer data from a PC to a Macintosh
Macintosh OS to Windows OS:
Seagate FreeAgent GoFlex drives includes the Paragon driver, which can make NTFS file systems usable in MacOS. Please see Document ID: 219103 for instructions on installing it. This is the best solution Seagate offers for transferring data between Windows and Mac computers. For non-GoFlex drives, Windows does not support the Macintosh file system and it cannot be read. However, Macintosh and Windows can read the FAT32 file system. Using a FAT32 formatted drive within the Macintosh environment is only recommended for a short period of time to transfer data. It is recommended that you divide the drive in 32GB volumes/partitions and format as FAT32.
Data corruption will be prevalent when using FAT32 over an extended period of time in a Macintosh.
Using a third-party disk utility that allows you to see Macintosh formatted volumes is an alternative to using FAT32 file system for the external hard drive.
MacOS to MacOS:
Some Seagate external drives, such as the FreeAgent Go for Mac and FreeAgent Desk for Mac, come formatted in MacOS Extended format, which is supported by Mac OS 8.1 and later. Others, which come formatted in NTFS, need to be reformatted in MacOS before you attempt to store data on the drive. See Document ID: 207851 for instructions. When you format your external hard drive, it should be formatted for Mac OS Extended. If you are transferring data from an OS 10 system to an OS 9 computer, or trying to access the data through OS 9 (with a drive formatted through OS 10), you will need to have installed OS 9 driverswhen you erase the drive. Otherwise, transferring data between OS 10 operating systems should work.
Helpful Apple articles:
Mac OS: About Mac OS Extended Volume Hard Drive Format or HFS+
Mac OS: Disk Is Available in Mac OS X But Not in Mac OS 9
MacOS energy-saver setting
Mac OS include an Energy Saver feature that can cause hard drives connected in or to the computer to spin down after a period of inactivity. If Mac OS sends a command to spin down to an external drive, the drive may stop being detected by the computer. To ensure that the Mac does not send a command to spin down your external drive, please see this article from Apple support.
Uncheck the Put the hard disk(s) to sleep when possible box in Energy Saver.
USB External Troubleshooter
First try these troubleshooting steps:
Try a different port Try a different cable Try a different computer Verify the drive light is on Try a different power outlet (Desktop Drives) Plug adapter directly into the wall if in a power strip (Desktop Drives) Verify that it the drive feels like it is getting power
For additional troubleshooting steps select your operating system:
Windows
Macintosh
For Windows check device manager and disk management in computer management:
Try the following Steps:
Hold the Windows Key ( ) down and press R Type compmgmt.msc into to the run box Select Device Manager on the left First check disk drives in the middle window If you see the drive is detected here continue reading. If not, click here Right click on the external drive listed under Disk Drives Click on Properties Click on the “Volumes” tab Click on Populate Document the disk number provided in this Window Click on Disk Management on the left hand side In the middle towards the bottom locate the disk number from earlier
Once located you will want to look for the following:
Does it say RAW or Unalloctated?
If the drive says RAW or unallocated and you have already tried a different port, cable, and computer but you need the data then you will want to consider data recovery.
If the drive is formatted correctly for Windows you should see the following information:
NTFS - If NTFS is missing then the file system has become corrupted. You can format the drive if you don’t need the data. Capacity - Check to see if the drive is correct for example if you have a 1TB drive it should say 931GB. Drive letter - Verify that the drive has a drive letter. If it is missing verify that other drives have a letter. If other drives have a letter but the external is missing then you can right- click and select change drive letter or path. Click Add then assign a letter and OK
If the drive was not detected under disk drives then check the following:
Within device manager look for unknown device, other device, or mass storage device with a yellow ! icon. Make sure to expand Universal Serial Bus controllers too.
If you see an unknown device or other device then right-click and select properties.
Under the general tab locate ‘Device Status’ and there may be an error.
You may see a code 10 or 28.
If you see Code 10 and have already tried another cable and computer then the drive has probably failed.
If you see Code 28 (this may work for others codes too, ie Code 43) then try the following: Close the window with the code Right-click on the device with the issue and select uninstall Shut the computer down and disconnect the drive Reboot with the drive disconnected Plug the drive into a different port You should see that it is installing device drivers Once the driver loads check to see if it is giving the same Code.
Note: If that fails, you will need to try to reload the USB drivers for the operating system by inserting your Windows Media, rebooting, and attempting a Repair/Restore.
Warning: This can be dangerous to your data and you should disconnect your external drive before attempting this.
Macintosh
If the drive is not showing on your desktop or within Finder check disk utility.
Applications>Utilities>Disk Utility
You should see the drive on the left hand side
You should see two entries - the top with the capacity and one indented below that.
Select the indented entry for your drive and click on the “Mount” button at the top of the Disk Utility.
If the indented entry for your drive is greyed out then that indicates some level of file system corruption.
Select the indented entry and then click on Verify Disk.
Once the Verify Disk process is complete it will suggest you repair the disk or tell you there is nothing wrong with it.
If this is not the only copy of your important data, then try to run the Repair Disk process to see if it resolves the file system corruption.
If this is the only copy of your important data, then we suggest running data recovery software on the drive to attempt to retrieve your files.
If the Repair Disk process fails to repair the disk then you will want to reformat it to see if you are dealing with a physical issue or a logical issue.
Warning: Formatting erases all data on the drive.
USB Device causes XP system to hang on reboot
This problem may occur if you have both USB 2.0 devices and USB 1.1 FDD devices connected to a Windows XP SP1-based computer. Because Windows XP SP1 does not support the USB 2.0 Legacy BIOS, the USB 1.1 device driver does not work correctly.
To work around this problem, turn off USB 2.0 Legacy BIOS support in the computer's BIOS Setup utility. For information about using the computer Setup utility to modify the BIOS settings, contact the manufacturer of your computer.
Additional Information:
Microsoft KB# 832577: The Computer Stops Responding During Startup
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How do I Troubleshoot SCSI/ATA hard drive combinations?
When SCSI drives are connected to the SCSI host adapter, with an ATA drive installed, you are unable to boot from the ATA drive. The SCSI host adapter and the ATA port on the motherboard could be set for the same IRQ or address or both. Check the following:
For the primary port, the ATA ports on the motherboard will likely be set to IRQ 14, and the I/O address will likely be set to 1F0-1F7. For the secondary port, the ATA ports on the motherboard will likely be set to IRQ 15, and the I/O address will likely be set to 170-177. The SCSI host adapter's IRQ and I/O address should not conflict with the above settings. If using a plug-in controller or host adapter with a BIOS, make sure the BIOS address does not conflict with the address settings of other cards or devices. Check the documentation for the motherboard or SCSI host adapter for detailed information on how to change these settings. If unavailable, contact the vendor of the ATA or SCSI host adapter.
Once these setting are properly implemented, your computer should be able to recognize available ATA and SCSI drives with no problem.
You are unable (or there is a long delay when trying) to boot from the SCSI drive.
The motherboard's BIOS might be "pinging" the ATA bus looking for an ATA drive. When using a SCSI drive as a boot device, there should not be an ATA drive physically attached as the Primary 0 (master) drive, and the CMOS settings for the Primary 0 drive should be set to "none" or "not installed". In addition, check the CMOS settings for the Primary 1, Secondary 0, and Secondary 1 drives. If any of those drives are not physically present, the corresponding settings should be set to "none" or "not installed" as well. If you are still unable to boot from the drive, make sure it has been properly prepared as a bootable drive - make sure it has been formatted and has active partitioning set.
The SCSI drive is not recognized at full capacity.
Make sure the SCSI host adapter's setting for "above 1GB support" is enabled. For drives larger than 8.4 Gbytes, enable the BIOS' INT13 Extensions.
If the drive is reporting less than its full factory capacity to the controller BIOS, it is possible that the drive may have been programmed to a smaller capacity (Seagate SCSI drives support a change capacity feature).
If this is the case, standard drives may be returned to full capacity (or reprogrammed to any capacity up to full capacity) using Seagate's SeaTools utility.
The SCSI drive is not performing optimally.
Try the following:
Make sure your card and motherboard's BIOS are optimally configured for performance. You might need to contact the manufacturer of the card for assistance with these options. Check your SCSI cable and the drives' ID, termination, and termination power settings. Make sure the cable is of good quality and is not coiled up inside the computer. Try to route SCSI ribbon cabling away from the power supply. If this is the only device attached internally, set the ID to 0 and terminate the drive. If there are 2 or more devices internally attached to the SCSI cable, set the boot drive to ID 0, set the other devices to any other unassigned SCSI ID (except 7, which is usually reserved for the SCSI host adapter), and terminate the drive that is physically at the end of the cable. Termination power should be set on both drives to match the requirements of the SCSI host adapter.
The following recommendation is DATA DESTRUCTIVE. Proceeding will ERASE ALL DATA FROM THE DRIVE. We recommend that you use the SCSI host adapter's utility to low-level format (or initialize) the SCSI drive. This will help ensure that the drive is properly communicating and optimally synchronized to the host adapter. If possible, BACKUP the drive(s) before following this procedure.
1. If this is not possible, and the data is needed, please consult a data recovery service to assist you in recovering your data. 2. A low-level format typically takes 45 - 60 minutes per gigabyte. The larger the drive, the longer the time required for completion. 3. DO NOT TERMINATE OR ABORT THE LOW-LEVEL FORMAT! The drive(s) can become permanently damaged.
After the low-level formats are completed, reboot the computer from a bootable system or recovery diskette and proceed to prepare the drive for use. In a DOS or Windows 95/98 environment:
1. Use FDISK to partition the drives as desired. Ensure that the C: partition is a "PRI-DOS, ACTIVE" partition.
2. After partitioning the drives, reboot the computer.
3. Use FORMAT to high-level format each partition on the SCSI drives. o Type format X:, where X is the drive letter of the drive you wish to format. o If you want to make the C: partition bootable, add the "/S" parameter to the end of the command to transfer the system files. (At the command prompt, type FORMAT C: /S)
Each partition should now be formatted to its full capacity, ready to store data.
How to turn on or turn off the FireWire or USB External Storage unit to ensure it is recognized in a Mac system.
The following power sequence must be followed for your system to properly detect your USB and/or FireWire External Storage unit:
When the Mac is OFF:
To TURN ON the External Drive and the Mac Computer:
1. Plug one end of the interface cable into the drive and the other end into your Mac's FireWire or USB Port. 2. Powering up the External Drive o For External Drives WITHOUT a power switch - connect the power cord into the power connector o For External Drives WITH a power switch - turn the power switch to the ON position.
...please allow 10 seconds for the drive to power up.
3. Power on the Mac.
To TURN OFF the Mac and External Drive:
1. Power down the Mac 2. Powering down the External Drive o For External Drives WITHOUT a power switch - disconnect the power cord from the power connector o For External Drives WITH a power switch - turn the power switch to the OFF position. 3. Disconnect the FireWire or USB interface cable from the port on the external drive and from the Mac (optional).
When the Mac is ON:
To TURN ON the External Drive:
1. Powering up the External Drive o For External Drives WITHOUT a power switch - connect the power cord into the Power Connector o For External Drives WITH a power switch - turn the power switch to the ON position.
...please allow 10 seconds for the drive to power up.
2. Plug one end of the interface cable into the drive and the other end into your computer's FireWire or USB Port. 3. Once connected and powered on, the drive will mount on your Mac's Desktop.
NOTE: The Icon for a USB External Drive differs from the above image.
To TURN OFF the External Drive:
1. Drag the External Drive to the Trash.
NOTE: The Icon for a USB External Drive differs from the above image.
2. Unplug one end of the cable from the drive, then the computer. 3. Powering down the External Drive o For External Drives WITHOUT a power switch - disconnect the power cord from the power connector o For External Drives WITH a power switch - turn the power switch to the OFF position. 4. Disconnect the FireWire or USB interface cable from the port on the external drive and from the Mac