Can I run multiple RAID arrays on a single RAID card?

You can run multiple arrays on the card. Arrays typically configured in BIOS. A driver will likley be required and supplied by Intel

It varries, but with a proper raid solution you can create multiple raid arrays out of distinct groups of disks, or even slice a single group of disks into multiple raid arrays. For example, you can take 3 disks and use part of each for a 3 way raid1, and the rest for a raid5, or take 5 disks and use part of each of them for a raid0 and part for a raid5.

Note that you can save a lot of money by skipping the hardware raid support and just using Linux software raid, which often is much more flexible.

For true hardware raid, you will need an appropriate driver, and usually application software to manage the raid from within the os. They also usually have a bios interface to allow you to configure the array before installing an OS.

The cheaper raid cards are in fact, fake raid, which is to say, just a bog standard AHCI SATA controller with special software/drivers (usually only for Windows) and bios extensions that implement the software raid. Linux will see the hardware for what it is, and see each of the individual disks. A software package called dmraid will recognize the raid metadata on the disks and configure the kernel device-mapper software raid driver to access the array, but this is nowhere near as well supported or reliable as the conventional Linux software raid ( mdadm ).