RAID question

[Darxide]

Maybe someone can answer a few questions for me?

How much of a performance gain do you really get from using RAID 0?

I was considering buying a Velociraptor for my new rig, but since my new mobo has RAID onboard, I thought I might try that instead. I mean by using 2 cheaper HDD's in stripe mode.
Would that setup outperform a single Velociraptor?

And how good are onboard RAID controllers? Do the boards have a hardware controller, or is it done with software? My mobo is the new DFI Lanparty 790FX, the one with the SB750.

Thanks.

[tiro_uspsss]

if ur just doing R0, onboard is fine..
what HDD u got now?

[Darxide]

I have 2 Hitachi Deskstars right now, not in RAID, just C: as the system disk, and D: for file storage. But I'm gonna retire them, because they're EIDE drives and I need SATA for the new mobo.

Also, I should add that I'm not concerned about storage for the new rig, I just need a fast system disk. I now have a NAS with 2 1TB WD EACS1000's in RAID1, so all my data is stored there. ( I know thats not 100% safe, so I use DVD-RAM to backup anything critical ).