Hi,
I just got a 2 TB Green WD20EZRX and I started using it in an USB 3.0 enclosure. Read speeds are as high as 150 MB/s. But when you write to it (even with a 4 GB video file), the speed goes up and down almost rhythmically between 90-10 MB/s. It looks like it is writing in bursts with pauses in between. Same file on the same machine written to WD Passport USB 3.0 can sustain around 100 MB/s speeds.
So is this a feature of the drive or should I get it replaced.
Thanks
You are very polite. Saying that is a feature lol.
Just for confirmation proposes please test it on your computer on another sata port or better on another computer … Just to confirm that the drive have a bad write head. Install hard disk sentinel and see the performance/ health and smart tab ( on smart tab right click mouse and change values to decimal) it think you will have write errors and 0 read errors. If that is the case its another way to confirm that the drive came DOA
I don’t have access to another computer and the pc I am using it is a mini pc so it doesn’t have an extra SATA port. But CrystalDiskInfo 6.5.2 x64 shows the SMART data and there are zero read and write errors. It has, however, 15914 UltraDMA CRC Error count. Does that mean there is an interface problem?
Exchange the sata cable and try several transfers and check smart values. If write errors increase i would exchange the drive
I think I finally fixed it. I put a jumper to limit the drive to SATA II (3 Gb/s). Now I am getting 150 MB/s sustained writes without fluctuation and UltraDMA errors are no longer increasing. So I guess the USB 3.0 external enclosure is not compatible with SATA III (6 Gb/s) although it says it is. Still don’t understand why it only affected writes and not reads. Anyway it looks like it’s working properly now.
glad you figured it out
