Testbed and Methods

The testbed configuration looks as follows:

• ASUS P3B-F mainboard;
• Intel Pentium III (Coppermine) 600MHz CPU;
• 2 x 128MB PC100 ECC SDRAM by Hyundai;
• IBM DPTA 372050 HDD;
• Matrox Millennium 4MB graphics card;
• Promise Ultra100 TX2 and Promise Ultra133 TX2 controllers;
• Windows 2000 Professional SP2.

ATA100 HDDs were tested with Promise Ultra100 TX2 controller (BIOS: 2.20.0.14 Drivers: 2.00.29).

The following software was used:

• HDTach 2.61;
• WinBench 99 2.0;
• Intel IOMeter 1999.10.20;
• FC-Test v0.3.

Before the tests the AAM register of all HDDs was set to OFF position (FAST mode) with the help of Hitachi Feature Tool Utility. For WinBench tests all the drives were formatted in FAT32 and NTFS as one logical drive with the default cluster (to format the drives in FAT32 we used Paragon Partition Manager utility). The tests were run four times each, the maximum result was taken for the diagrams. The drives didn't cool down between the tests. The tests in Intel IOMeter were run in SequentialRead, SequentialWrite, DataBase, WorkStation, FileServer and WebServer patterns. If you are looking for the detailed description of these patterns, please, see our previous articles.

The participating HDDs had the following firmware versions:

• IBM Deskstar 180GXP IC35L180AVV207-1 - V26OA63A;
• Maxtor DiamondMax Plus 9 6Y200P0 - YAR41VW0;
• WD2000JB - 63.13À63;
• WD2500JB - 15.05R15.

The different firmware versions of WD2500JB and WD2000JB already imply significant differences in their performance.

Performance

HDTach 2.61

HDTach is a questionable test, in my opinion. So, we don’t dwell upon its results too much and only compare the drives by their average access time and burst rate parameters.

Wow! WD2500JB with its higher-density platters has better access time than WD2000JB! Usually, this happens when the capacity of the platters is not used to the full extent. Once, I got my fingers burnt on Maxtor drives, and now I suspect everyone and everything. :)

So, maybe the design of WD2500JB is better described by the 63x4 formula, rather than 83x3? Read speed values also indicate this…

I abhorred the idea to take such a pricey thing to pieces, but was eager to know the truth. That’s when a new “bloodless” method of checking the number of platters in a drive dawned upon me: weighing! Drives belonging to one family are usually manufactured using the same case. So, the different weight of two models with different storage capacities would indicate a different number of platters and heads used to build it. Having collected weight statistics for various models, you can guess the number of platters in a new drive with a high degree of accuracy.

In our case, we have two WD drives that both have three platters and six heads (at least, theoretically). So, let’s put them onto the SCOUT II scales (SCA210 model) from Ohaus.

As you see, both drives are equally heavy. Since WD2000JB doesn’t have four platter-design for sure, WD2500JB is no longer suspected! Just like in a detective story a-la Erle Stanley Gardner…:)