>Al,
>>>>>>- 4 disks in RAID10 for Windows and the swap file ( C: )
>>>>>This causes one highly raised eyebrow - what is swapped here to need that setup ? Especially Raid10 for a swap file ?
>>>>>Better image your boot partition and Raid0 the swap file, if necessary at all
>>>>
>>>>The swap file will get hammered in low memory conditions, so yes, a RAID0 at least will probably help. If the OS (without swap file) is put on yet another volume, for redundancy that would need to be RAID1 anyways. Add 2 more drives for RAID0 on the swap file, and you're up to 4 drives. That may be why RAID10 is recommended here.
>>>
>>>Still doesn't fly with me, as you can prepare the installation to use other disks for swap. These other disks will be used if the room on the first disk is not enough or the first swap disk has problems. Analogous thinking from client OS behaviour, doubt if server behaves differently.
>>
>>Not sure I follow you here - can you expand on this?
>
>AFAIK the swap file handling is already fault tolerant in windows. If you set swap file on different partions/disks, ONLY the first will be used until size doesn't fit or errors occur. So if you place aditional swap files on other partitions, you are safe as in covered against faults. You will have lower perf when the swap is using a partition <> primary swap, but that is only until you hotswap the disks. So with that approach you get better reading perf on OS partition (if controller is smart) by going Raid1 there and have swap file performance separated and high in read/write via Raid0.

Thanks, Thomas. For lurkers, I've found a couple of useful links on this topic:
http://www.petri.co.il/pagefile_optimization.htm
and especially
http://support.microsoft.com/?kbid=197379