I hear onboard RAID is not as effective as aftermarket PCI controllers.. Any experience on this???
yes i do have experience on this, and the short answer is no, there is no real difference. there might exist, in some parts of the world, crappy no name north bridges, that support raid, but really just have software raid, but as long as its an Intel or an Nforce chipset, its a hardware level raid, and it will perform as well as an ad in card, if not faster in some instances because of hte lower latency from the north bridge, compared to an ad in card that has to go through the PCI/PCix/PCie bus then the northbridge, then to the processor.
altho realistically, you would need a RAM drive to test that, because hard drives are far to slow to push the bandwidth.
This is true (that there is essentially no difference) for RAID 0 and RAID 1 implementations, but not RAID 5.
Software controllers/on-board controllers do the XOR parity calculation required for RAID 5 in software, which takes a lot of CPU power and severely slows down the write speed of the array.
Hardware controllers have dedicated processors for doing the XOR calculation and will outperform motherboard/software controllers by a long shot.
yes this is true, i should have been a bit more thorough, the nforce 4 chipset and higher supports SOME raid modes, most support at least 0, 1, 5, and JBOD. you would honestly need to look at the exact specs of that northbridge, to be able to tell. i would aslo agree with others that it would be a bad idea to depend on that specific northbridge for data integrity. its also worth noting that ad in cards often have a plethora of extra features, and extra software for rescuing arrays gone bad. my original point was simply that, the average person will not see the difference between an a chipset raid or a separate controller. also worth noting is there are some motherboards (usually workstation or server class) that have actual dedicated RAID chips on them, that are not part of the northbridge/southbridge solution.
what kind of raid system are you planning on setting up? because that is what will determine whether or not you should use onboard or an ad in. if you just want to RAID two discs in raid 0 then there is no point in an ad in controller, because you have no integrity, and just raiding two discs hardly justifies a $150 controller.