Depends on the hardware involved. And what OS. Windows is not very forgiving when changing hardware that involves drivers, such as chipsets. Linux is much better at this. But RAID is very dependent upon the setup of the RAID array, which is tied into the hardware involved. Most times you cannot even see a RAID if you chnage the drives to a different motherboard even if it does support RAID.
Another trap is changing hardware that is similar and then not updating drivers. This can have some weird effects, like random crashes, which can be almost impossible to troubleshoot. Best option is a clean install if different hardwae is involved.
Cheers
Mick