You don't need to change the BIOS to use it as an IDE card - use one drive and set it as the array and it will work fine. There will be a slight increase in boot time as the card's BIOS screen comes up and it detects the drive, but that's more than made up for with the increase in drive speed over the usual ATA 33 speed of the type of motherboard this card would typically be used with. If it were mine, I'd update the BIOS to the latest one (if it isn't already) and use it.
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