simple question about Disk Mark

[riow]

Hi there, I'm new here.

I found a page about PassMark - Disk Mark for harddisk at http://www.harddrivebenchmark.net/high_end_drives.html. Could anyone let me know about how the marks are got?

[David (PassMark)]

These 2 pages cover most of the details,
http://www.harddrivebenchmark.net/hdd_test_info.html
http://www.harddrivebenchmark.net/graph_notes.html

[riow]

I'd like to modestly consult a question. I've two harddisks which are WD10EARS and WD1600HLFS. I use CrystalDiskMark 3.0.1 to measure them and both the results are almost identical in which the screenshots are http://img193.imageshack.us/i/wd10ears.png/ and http://img338.imageshack.us/i/wd1600hlfs.png/.
I measured them in the same computer, the same computer condition, and environment. However from the PassMark Disk Mark harddisks list, they have different ratings in 607 and 731 respectively. Does it mean that the CrystalDiskMark is no good to determine actual speed of different harddisks? Please advice.

[David (PassMark)]

The results in your screen shots are not the same at all.

Disk #1 got 0.5MB/sec in the 4K seek test.
Disk #2 got 0.9MB/sec in the 4K seek test.
This is an 80% increase.
Even the sequential tests showed a 10% difference.
So there is no reason to think these drives have the same performance.

Further, each of your drives was probably not in the same initial state in terms of free space and fragmentation.

Also the numbers in our charts are averages from many different systems. So some variation is to be expected even if the drives really did perform the same.

[riow]

I'm not skillful in reading the benchmark test results. Thanks passmark for the explanations and the informative harddisk lists offered for ref!