How to activate write through

Hi,

I have set up an PowerEdge 2600 Server running Windows Server 2003. Everything is running quite well, but I didn't manage to set the write policy to write through. By searching the Dell-Database I only found out, how to set the raid-controller to write hrough in the perc-bios. But when I look at the policies of my raid-system in Windows, the option optimize for performance is activated (which seems to include the write-back policy), and I can't change the setting in this window. Also when I look at the Raid-System in Dell-Open-Manage it is set to write-back.

So if anyone knows how to change this, please tell me :)

Thanks

Felix