[cwes]

Yes you can use the defragmentation utility with a raid 0 array. Windows will only work with the logical drive, the raid controller will take care of the rest (i.e. on which disk the parts of the files are actually stored).

Shouldn't you already have configured your raid 0 array, please consider the following advice:

Using a raid 0 array bears a major danger: If one of the two (or more) harddisks of the array is damaged, you will lose all data on the array.

You might say: "So what?" Well, the problem is that it is muche more likely that one out of two harddisks is damaged than one out of one harddisk is damaged. Therefore, by using a raid 0 array, you expose yourself to a much higher risk of losing all data on the harddrives. Don't do it unless you really need it.

You usually need it if you have lots (LOTS! stuff like very large files, veeeeery many small files) of temporary data that has to be moved around quickly and isn't needed (or archived elsewhere) long term.

If you want to use raid 0 just for a large logical hdd, please consider using two logical hdds instead. You will have the same amount of space and there are no real drawbacks unless you need the raid 0 for the stuff mentioned above.

HTH