Windows 7 - SSD Raid 0 - Unusual speed difference

I`ve just purchased 2 x Ocz 60 gb SSD`s and set them up in Raid 0 .

I was expecting a huge performance boost but was pretty dissapointed .

However benchmarking figures are pretty impressive , just doesn`t seem

to come through in real world use .

Now the strange part - when benchmarking in HD Tune Pro it shows the

read speed between 200 mb/s and 270 mb/s until it reaches about the 35gb

distance then it jumps up to around 410mb/s till the end of the disk (119gb) .

During the first part (upto 35 gb mark) the drives are noisy (not excessively)

but after that it goes quiet through to the end .

One other thing - in Everest it lists two storage controllers :

1- AMD AHCI Compatible Raid Controller

2`nd listed is - JMicron JMB36X Controller

Any thoughts on these would be appreciated .