Different speeds for two identical USB sticks

Now had time to return to this. Decided to run some controlled tests; I also remembered that I had another SanDisk Ultra 32GB USB3 drive, this one in a fetching shade of black though a few months younger than the other two, so I included it in the tests. Turned out to have been a useful move.

I prepared a test set of files and folders of 863 files totalling 2.80GB. I also copied all the data of each drive before starting! As with original post I used FreeFileSync (FFS) to copy the files and give me transfer rate and time. I also stopped any other USB traffic.

The test sequence was:

Plug drive 1 directly into port 1 in a USB3 card in the back of the PC
Quick format each drive
Create a Test folder on the drive
Start FFS, set up the Sync pair, click Compare
Check it is reporting 863 files & 2.80GB to sync
Click Synchronize
Wait for completion and record transfer rate and time

Repeat for drive 2 in port 2
Repeat for drive 3 in port 4 (using port 3 was a little tight)

Rotate the 3 drives 1 port "clockwise" around the 3 ports and repeat
Rotate the 3 drives 1 port "clockwise" around the 3 ports and repeat

By now all 3 drives have been tested in all 3 ports.

Repeat the above 9 tests using the USB3 extension leads that I normally use.

These are the results:

Plugged directly into the USB3 ports

Port	1			2			4		Average
	Speed	Time		Speed	Time		Speed	Time	Speed	Time
	(MB/s)	(m:s)		(MB/s)	(m:s)		(MB/s)	(m:s)	(MB/s)	(m:s)
Black drive	23.5	02:02		24.7	01:56		24.1	01:59	24.1	01:59
Blue drive	13.6	03:31		14.8	03:13		14.6	03:16	14.3	03:20
Red drive	17.1	02:48		17.7	02:41		17.1	02:47	17.3	02:45

Via 1m extension lead

Port	1			2			4		Average
	Speed	Time		Speed	Time		Speed	Time	Speed	Time
	(MB/s)	(m:s)		(MB/s)	(m:s)		(MB/s)	(m:s)	(MB/s)	(m:s)
Black drive	23.1	02:04		22.03	02:08		23.8	02:00	23.0	02:04
Blue drive	15.3	03:07		15.7	03:02		16.4	02:54	15.8	03:01
Red drive	17.1	02:48		17.1	02:48		16.1	02:57	16.8	02:51

Some conclusions:

• The black (newer) drive was considerable quicker than blue or red
• The red drive, despite the experience reported in the original post, was quicker than the blue drive
• Using 1m extension lead made no significant difference to performance.

Clearly using a different set of files, more small files for example, would change the performance.
It would seem that the original experience posted, and these figures, reflect Helmut's post that natural variations in the chips being used (and the firmware version?) give these sort of differences. I had - perhaps naively - assumed that two apparently identical USB drives would give the same (or nearly so) result.

Thanks for sharing your test results, that's all 'good to know' stuff.

If you're interested in performing a few more tests, consider this;

Performing a full format, instead of a quick format, will mark all the defective sectors possibly resulting in a defined change to the storage architecture.

I haven't tested this theory, however; it makes sense in my head and I would be surprised if it doesn't change the test results by some measurable amount.

I don't want to wear out my drives!

I had previously run an Error Check via Windows Explorer/Properties/Tools and no errors were reported.

I'm going to mark this as solved as I feel what we've seen is the consequences of "cheap as chips" devices and their variability. I suppose that begs the question as to how one can get high quality, consistent, USB sticks, though probably not worth the cost? But at least we have, perhaps, a better understanding of such things.

Hello @tpriest,
Excellent and methodical work on the testing and accumulation of the data results.

I often perform things like this [ my OCD I think mainly ] to get to a definitive conclusion, if possible.

I should have said I was more interested in the differences between devices than the absolute speeds.

I will leave this on my 'to do' list but no idea when I'll get to it. I know all my USB sticks are busy with dedicated content.

I'll watch for a sale online and buy a couple more for testing. My GF looks irritated when I say the 10 or 12 I own aren't available for her use. LOL

tpriest, a few questions...

What were the size and specs (3.0 or x.x) of the 3 you tested?
Formatted NTFS?
Were all files on the 3 disks the same or different?

I will try to obtain 2 of the same new USB drives, full format them. verify disk integrity with a third party app, load them with the same blend of large & small files and run a battery of performance tests.

W10 Tweaker said:

What were the size and specs (3.0 or x.x) of the 3 you tested?

All 32GB; externally labelled USB 3.0 though Device Properties says USB SanDisk 3.2Gen1 USB Device

W10 Tweaker said:

Formatted NTFS?

Yes

W10 Tweaker said:

Were all files on the 3 disks the same or different?

Exactly the same set of files being copied to the 3 drives in all the tests.

tpriest said:

All 32GB; externally labelled USB 3.0 though Device Properties says USB SanDisk 3.2Gen1 USB Device
Yes

Exactly the same set of files being copied to the 3 drives in all the tests.

Excellent, thanks for the update.

I will try to get at this testing in the next month, start a new thread, and post a link here for reference.

Thanks for your efforts and contributing to our knowledge base.