HD Tune - Problem with my Raptor ??

[yngndrw]

Hi guys (And girls),

I have been looking at my Hard Disk performance with HD Tune and I think I have a problem with my Raptor.

It's a very old 10,000RPM Raptor 74GB (Think it's actually only SATA1). I have it on a 680i port, with two 500GB Seagates in RAID0 on the same controller.

Also note that I was using the computer for internet while the tests were in progress, so that may explain the large dip.

Here's the tests for the Raptor (Done twice):



Here's the comparison test for the Seagate Array:



It alarms me that the Raptor's transfer rate goes down over the time of the test. Is this normal or do I have a problem ?
Would it be worth me dropping the Raptor and using 4x Seagates in RAID01 (Or 10 ?) and having them as one big drive ?

Other info:
The HDDs are all cooled by a 120mm fan.
The model number of the Raptor is: WD740GD-00FLA0
The model of the Seagates is: Barracuda 7200.10 500GB
The Raptor is my C drive. (Running Vista x86.)
The Seagates are just a games drive.

Thanks for any help,
-Andrew.