There are a lot of benchmarks to measure the speed of reading from the drive’s buffer, but unfortunately few of them are free from certain deficiencies. For example, the burst rate may be measured using small-size data blocks (in compliance with the old ATA/ATAPI specifications). Or the number of iterations may be dubious, too.
That’s why I can do no better than to use a test whose operation is well known to me. Moreover, IOMark is capable of measuring the speed of writing into the buffer which is perhaps an even more interesting parameter than the read speed.
The first test was performed with the drive attached to a Promise S150 II TX2+ controller.
The speed seems to be limited by the controller’s bandwidth (the controller is plugged into an ordinary PCI slot). Let’s try to attach the drive through the chipset then.
This looks true to life indeed. At least, the burst rate is very near the theoretical maximum of the Serial ATA-150 interface.
And now let’s see what we have with the previous-generation Raptors.
The two samples behave like twin brothers in this test and the write-into-buffer speed is lower than the read-from-the buffer speed with both of them. As you’ve seen above, these two speeds are almost identical with the WD1500AHFD.
Here’s a summary for this test – the maximum read and write speeds are compared:
The Raptor X is obviously better than the previous-generation drives in this parameter, especially when it comes to writing into the buffer.