Western Digital 320GB Scorpio Black

The Western Digital 320GB Scorpio Black is a solid performer among the 7200 rpm crowd.

It’s useful to compare it to its sibling the Western Digital 500GB Scorpio Blue, the latter being a better choice if your intent is to store 250GB or more of data.

See the review of the Intel X25-M solid state drive for more performance data; this is one drive that performs very nicely on real-world tasks.

DiskTester results

Test mule: MacBook Pro (Oct 2008 unibody) 2.8GHz 
SATA hardware: internal SATA II connector
Driver: Apple standard
Drive model: WD3200BEKT

Get your own copy of DiskTester for testing your drives, RAID, network, etc.

Sequential sustained transfer

These are excellent results for a laptop hard drive in late 2008.

# Sequential sustained transfer
----- Averages for "wd320" (512MB/start, 3 iterations) -----
Chunk Size    Write MB/sec    Read MB/sec
    32K           48.2            68.7   
    64K           61.7            80.8   
   128K           70.6            81.3   
   256K           74.8            80.8   
   512K           76.4            80.9   
    1MB           76.5            81.4   
    2MB           76.9            80.2   
    4MB           75.2            80.6   
    8MB           77.0            80.4   
   16MB           76.8            80.5   
   32MB           77.2            80.5  

Speed across the drive (area test)

These are very good speeds, but note that performance drops off quickly as the drive fills up. Laptop users storing more than 200GB of data should look carefully at the 500GB Scorpio Blue.

----- Averages for "wd320" (512MB/1MB, 3 iterations) -----
Area (295.9GB)    Write MB/sec    Read MB/sec
       0%             77.3            80.8   
      10%             76.1            79.3   
      20%             74.2            76.9   
      30%             71.8            74.5   
      40%             71.3            71.2   
      50%             66.8            67.6   
      60%             63.1            62.2   
      70%             59.6            59.2   
      80%             54.4            54.4   
      90%             48.8            48.8   
     100%             41.5            40.9   
Average write speed across the volume: 64.1MB/sec
Average read speed across the volume: 65.1MB/sec
----- Averages for "wd320" (512MB/32MB, 3 iterations) -----
Area (295.9GB)    Write MB/sec    Read MB/sec
       0%             77.0            80.8   
      10%             76.3            79.4   
      20%             73.2            76.6   
      30%             71.9            73.9   
      40%             71.0            71.6   
      50%             66.8            67.5   
      60%             62.9            62.7   
      70%             59.6            58.9   
      80%             54.5            54.4   
      90%             48.9            48.9   
     100%             41.7            40.6   
Average write speed across the volume: 64.0MB/sec
Average read speed across the volume: 65.0MB/sec

Create and read files

This test times how long it takes to create and flush files to disk, and to read them back, with the Mac OS X cache bypassed so as to reflect actual hard drive performance. The test is run on empty freshly-formatted drive.

With the advent of “stutter” in mediocre solid state drives, it’s not a bad idea to look at the consistency of performance.

Variance of 10MB file creation times (ms)