Swoping raid cards?

Hello all

I found out that my raid card is not compatible with OS 10.4

the card is a sonnettech raid 66 card.

I would like to upgrade to a compatible card like sonnettech raid 133.


my question is; do I have to format the hardrives when I install the new 
card? or can I just plug them into the new card and boot up with the 
existing os and apps on the striped Harddrives?

I want to avoid formatting cause I have much stuff configed like itunes, 
iphoto etc....everything is backed up, but I like everything as is.


Thanks for your time!