| It will improve sustained transfer rates, but that might not be a large performance boost for you, depending on what you do.
In terms of booting from the array, you'd need a card that comes with it's own BIOS. If the card doesn't come with it's own BIOS, then there's no chance of getting your system to boot from it. As to the card, it may or may not come with instructions... I assume you have a motherboard that doesn't have any RAID support on it?
Also, as you're changing the boot device, there's a possibility you might need to re-install Windows too.
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