Howdy. I'm having persisting poor USB3 performance on thumb drive in both front and rear ports, device is Sandisk Ultra 32GB USB3.
When copying from int SATA HDD to ext USB3 HDD I'm getting stable 75-90MB/s, however when I'm using a thumb drive, that speed fluctuates between 5-27MB/s, only twice in the last few weeks did I get 55MB/s (stable for ~25GB so it's not irregular spike). The power/data light goes off frequently, leaving the copying hanging for few seconds to 20+ seconds at a time, only to resume at slow speed, I'm baffled by this behaviour, which occurs with other USB(2) thumb drive.
USB3 driver is up to date, windows (7/x64) is up to date, disk management set to "Better performance", AV turned off for testing purpose. I've had a look online and nothing has fixed my problem. What am I missing?
Cheers
There is nothing wrong with your computer or it's USB3 ports. You bought a cheap low end USB3 drive with poor write performance. Having a brief glance at the Amazon reviews for this particular drive you bought (SDCZ48-032G-U46) shows that people are getting around 60-70MB/s read speeds but around 10MB/s write speeds.
Amazon reviews for your reference:
http://www.amazon.com/SanDisk-Ultra-Flash-Drive-SDCZ48-032G-…
If you are after a high performance USB3 drive I would suggest looking at the SanDisk Extreme CZ80 or the newer SanDisk Extreme PRO CZ88. In the end you get what you pay for, cheap USB's will usually have cheap controllers which means lower performance.
The Sandisk CZ80's are currently on sale at Amazon for a very reasonable price at the moment.
Sandisk CZ80:
http://www.amazon.com/SanDisk-Extreme-Transfer-SDCZ80-064G-G…
Sandisk CZ88:
http://www.amazon.com/SanDisk-Extreme-128BG-Speeds-SDCZ88-12…