If its a Hardware RAID config eg Press (F4) or (Ctrl S) during the POST sequence then all the data on the RAID array will remain there as long as you dont remove or delete the the array by going back into that setup and deleting it.

After you have installed RAID drivers in Windows then you will see that single drive made of 2 physical drives apear again with all data in tact.

RAID 0 is a performance array so 1 HDD dies ALL DATA is gone.