Change Allocation unit size with RAID 0 stripe 128 or not?

[copnas]

Just got a Gigabyte GA-990FXA-UD5 Motherboard and Configurated my
2x Western Digital Black WD1002FAEX 1TB Harddisks RAID 0 Stripe size 128, Cache Write Back on the two GSATA slots.
The avg. size of my files stored in the disks will be over 128k so I decided to have a 128k
stripe size.

What allocation unit size should I configure in Windows? (Windows Server 2008 64bit)
My RAID is 128k should I configure the Allocation size the same?
Do this two Configurations (stripe size / Allocation size) interact one to each other?

 

[HugoStiglitz]

as a general rule the smaller the files you will be working with the smaller stripe size to set your raid to.

for windows performance a smaller size would be reccomended.
working with large files e.g. movies & such a larger stripe size would be better

 

[copnas]

Yes sure, I do understand the raid stripe configuration and how it has to be set up.
The part which I don't get is how does Allocation unit size interfere with stripe size.
As I said RAID 0 with stripe size 128k, now RAID "knows" it has to "split" any file 128k to the one disk
and 128k to the other disk. Now if I configure windows to has for example 512k, which of the two configurations will be true?
Will the RAID obey to the RAID configuration (128) or to the windows configuration(512) ?