on board raid vs pci raid.

[allan_leung]

Hello

Is there disadvantage on onboard raid? Someone once told me it's slower since it's ONBOARD.

Is it always better to get PCI raid?

 

[Ice Czar]

well migrating an array to your next mobo is problematic, as is loosing access to the array in the event of a mobo failure

I wrote off my first RAID array, just for that reason, mobo died and I didnt want to choose the next based on the RAID controller

a RAID card also offers the possibility of a much larger stripe width (number of drives) with up to 12 channels (IDE) or more if SCSI, large onboard caches, dedicated XOR Processors for RAID5 parity calculations, more supported RAID levels...

and while onboard controllers are limited to either 133MB/s or in the case of a "true" SATA 150MB/s throughput, a PCI RAID card in a 64bit PCI slot can offer several orders higher throughput depending on the card, the slot, number and types of drives, RAID level ect.

Of course 64bit slots are normally only in server\workstation mobos