Slow Speeds - 1TB Extreme Portable to SanDisk 2TB Extreme PRO

[Rochambeaux]

Transferring large number of RAW and JPG image files from a 1TB Extreme to a 2 TB Extreme Pro drive.

2TB Extreme Pro (formatted NTFS and empty) connected to USB 3.2 Gen 2x2 Type-C, 1 TB Extreme USB 3.2 Gen 2.

Using supplied Sandisk cables. Files average around 20MB each - no large video, etc.

93.5 GB took around 45 minutes to transfer - File Explorer shows ~ 32-35 MB/s which I believe translates to 296 MPS.

If correct this is far below the rated speed of both drives - what’s going on?

[mslap01]

Try reverting the USB-C cable - worked for me…don’t ask me why.

Extremely slow

I am trying to figure out why my SSD’s are running so slow (I purchased two 500gb Extreme SSD’s). Connected to both USB-C and USB-A 3.1 ports on an Asus Rog Strix X470-F motherboard, both types of 3.1 ports are listing the following speeds on CrystalDiskMark 6.0.2 x64: Read:44.40MB/s Write:43.60MB/s These are nowhere near the advertised *Up to* 500MB/s Is there a firmware update or something that I am missing. I truly don’t understand how they can be running so slow. Any help would be greatl…

[Rochambeaux]

Do you mean reversing the cable??

[mslap01]

Yes, correct - assuming it is USB-C cable - put the end which is in the drive into the computer and vice versa.

[DAB1783]

I have a 2TB PRO and get those speeds if I use a different cable other than the one supplied. If its not a 10K capable cable I get 45MB/s with the right one I get 1080MB/s. So make sure its the original cable and its in good condition.

Also I would change the device properties in Window Device Manager for ‘Better Performance’ and ‘Enable Write Cache’. Not your issue, but helps speed things up a little.

[H-Gary]

The rated speeds of SanDisk Extreme drives (1,050 MB/s to 2,000 MB/s) are measured using sequential transfers of single, massive files. Transferring thousands of small files reduces these speeds because advertised rates apply only to single-file transfers, and Windows File Explorer slows down when processing individual files sequentially.

To achieve speeds closer to the drive limits, try these fixes:

1. Use a third-party file copying or backup utility: Utilities like FastCopy or TeraCopy bypass standard Windows Explorer limitations and handle small-file overhead much faster.

2. Zip the files first: Archive the folders into a single, uncompressed .zip or .tar file before moving them, and then unzip them on the destination drive.

3. Use the Command Line (Robocopy): Windows has a built-in tool called Robocopy that handles large batches of files better than File Explorer.

4. Check the drive formatting: Usually, exFAT drives perform well when transferring a massive number of small files. Additionally, disk cloning software is significantly faster for data-transfer tasks.

Read also: USB Transfer Speed and the Factors That Affect It