Motherboard Hardware Raid:

- Advantages:
- OS Independence
- Easier to setup and use
- Disadvantages:
- Motherboard dependence. It may require an identical model and firmware to transfer RAID hard drives.
- Typically slower to boot

Software RAID:

- Advantages:
- Motherboard independence
- Portable toward systems with a similar operating system
- Disadvantages:
- Will not be able to rebuild RAID volumes that have been created via Hardware
- Dual boot OS'es will not recognize each other's software RAID volumes

Other considerations:
– Newer computers would have fast CPUs that enhances software RAID performance to be on par with hardware RAID.
– Linux users may have access to more advanced RAID config, such as RAID50

My answer: when it is about servers and non-dual boot setups, go for software RAID if an expensive dedicated hardware RAID card is not being an option. Motherboard (fake) RAID has no real advantages on newer computers.