WD10EARS Copy Speed

WD Internal Drives Desktop & Mobile Drives
1

I recently bought a Green WD10EARS. It is supposed to have 64 Mb cache. When I start copying a file, the transfer rate is good (around 55 KB/s) but a the copy process continues, the transfer rate falls exponentially till 20 KB/s.

My PC Specs are:

Intel Core 2 Duo 2.93 GHz E7500

Kingston 2 GB DDR2

Intel DG41RQ Motherboard

HP DVD Writer

NVIDIA 9600GT 512 MB Graphics Card.

2

55 KB/s is very bad. Did you mean 55 MB/s?

Are you copying files between different locations on the same drive?

The WD10EARS is an Advanced Format drive. Therefore your partitions need to be aligned to the drive’s 4KB physical sectors. Which OS are you using? Have you installed any jumpers on your drive?

Could we see a read benchmark graph, eg HD Tune?

http://www.hdtune.com

3

Sorry! I meant 55 MB/s and 20 MB/s.

I am using Windows 7 Ultimate 32-bit.

I have used Acronis Adv Format tool to check if my partitions are aligned and it reports that ther are optimally allinged.

The data transfer is between the partiions.

Here is the HD Tune Screenshot:

4

ISTM that your benchmark graph is very unattractive. :frowning:

The numerous dips would suggest that the drive is having difficulty reading, and that this difficulty exists from outside zone to inner zone. I’m not an expert, but I suspect that the drive may have a weak head. Alternatively, it could be that other Windows tasks are interfering with the test.

I would perform a complete surface scan using MHDD. MHDD is a DOS based utility that will identify “slow” sectors, ie those that require several retries before they can be read without error.

Google turns up the following examples of benchmark results that look much cleaner than your own:

HD Tune benchmark graphs for WD10EARS-00MVWB0:
http://img822.imageshack.us/img822/6484/97803426.png
http://img405.imageshack.us/img405/9994/hdtunebenchmarkwdcwd10e.png

HD Tune benchmark graphs for WD20EARS-00MVWB0:
http://i93.photobucket.com/albums/l53/popeye0/WD20EARS/015_WD20EARS.jpg
http://img.danawa.com/images/descFiles/2/836/1835470_1_1290686431.jpg ISTM that your benchmark graph is very unattractive. :frowning:

The numerous dips would suggest that the drive is having difficulty reading, and that this difficulty exists from outside zone to inner zone. I’m not an expert, but I suspect that the drive may have a weak head. Alternatively, it could be that other Windows tasks are interfering with the test.

I would perform a complete surface scan using MHDD. MHDD is a DOS based utility that will identify “slow” sectors, ie those that require several retries before they can be read without error.

Google turns up the following examples of benchmark results that look much cleaner than your own:

HD Tune benchmark graphs for WD10EARS-00MVWB0:
http://img822.imageshack.us/img822/6484/97803426.png
http://img405.imageshack.us/img405/9994/hdtunebenchmarkwdcwd10e.png

HD Tune benchmark graphs for WD20EARS-00MVWB0:
http://i93.photobucket.com/albums/l53/popeye0/WD20EARS/015_WD20EARS.jpg
http://img.danawa.com/images/descFiles/2/836/1835470_1_1290686431.jpg

ISTM that you should be expecting a read transfer rate of about 113MB/s at the outermost zone and about 50MB/s at the innermost. This corresponds to a difference of about 2:1 between the outer and inner diameters of the drive. Since you are reading from one partition and then writing to another partition on the same drive, you would expect that the maximum possible read/write transfer rate would be halved, ie 56MB/s at the outer zone, and 25MB/s at the inner zone. If you are copying from outer zone to inner zone, then the figure would be somewhere in between. I suspect that your initial high result could be due to the effect of caching, either by the drive itself, or by your OS. Afterwards the figure should settle down to the sustained transfer rate specification of your drive, ie the data rate to and from the platters, rather than the data rate into and out of cache memory.

BTW, if we imagine a curve of best fit in place of your jagged benchmark graph, we could estimate a maximum of 113MB/s at the outermost zone, and about 90MB/s at the innermost zone. This is not the typical 2:1 ratio that we would expect to find. Instead, it appears to me that your WD10EARS drive may actually be a WD20EARS that has been short stroked. I say this because if you examine the 1000GB point on the WD20EARS graphs, the transfer rate is about 90MB/s, which corresponds to the transfer rate at the end of your own WD10EARS drive. To me this suggests that your drive should be performing much faster than other WD10EARS drives, if not for the apparent head problem.

5

Well my hard disk IS WD10EARS that much I am sure!

As far as MHDD is concerned, it reports an error saying it can’t detect my disk. Also, in it’s documentations, it said not to run MHDD from the drive on which diagnosis is to be done…

6

You can run MHDD from a bootable floppy, flash drive, or CD.

MHDD expects to see a standard IDE drive, so try configuring your SATA controller for legacy or IDE compatibility mode in your BIOS setup.

You may need to launch MHDD with the /ENABLEPRIMARY switch.

As for my comment regarding your drive’s performance, I did not mean to suggest that it is in fact anything other than a genuine WD10EARS. I was merely making the observation that it behaves like a short-stroked WD20EARS. ISTM that WD could easily manufacture the one 2TB drive, and then sell it as either a WD20EARS or a WD10EARS. In fact it would be interesting to compare the weight of your drive against a WD20EARS. Normally we would expect a difference corresponding to the weight of 2 platters and 4 heads. You could also compare the DCM number (Drive Configuration Matrix) on the label against other WD10EARS and WD20EARS drives.

7

Problem Solved!

I have got a replacement for the drive. It seems the drive was defective.