HDDs not detected on new X58 Motherboard

I am putting together a new core i7 system, and I have two SATAII hard drives that I used in my previous C2D system without problem. My new system came together nicely, but the Bios of my MSI X58 Platinum motherboard won't detect either of my SATA HDDs. Strangely, my SATA DVD-R drive is detected just fine.

I've tried switching cables and ports, but nothing seems to work. I've even tried putting in a few other SATA drives and none of them are detected either (so it's not a problem with the HDDs themselves). I don't have any IDE devices connected.

Any ideas? Thanks!