Supermicro RAID rebuild issues

[arguseye]

Hello,
My applications slow and fail while the RAID rebuilds after a failed drive. Using the onboard Intel RAID controller. Do I need a seperate RAID controller or will increased processor & memory help?

 

[daniel528]

What kind of motherboard? Do you have latest BIOS upgrade?

 

[foscooter]

What mobo? What RAM? What HDDs?

RAID 0 or 1?