I've got ASUS Sabertooth 990FX mobo (rev. 1.0) with AMD SB950 controller for SATAIII drives and JMicron JMB362 for SATAII drives.
I've got Intel 330 SSD hooked up to SATAIII (AMD) controller and it works perfectly, however, when I try to connect my Seagate SATA 6Gb/s drive (ST1500DL003-9VT16L) to AMD controller it never gets recognized in BIOS, like it's not there at all, no errors, nothing, even though I can hear the drive spinning up.
Currently I'm using this drive in legacy mode (with JMicron controller) and it works perfectly, apart from being slowed down due to the slower interface.
What could possibly cause this? Unfortunately, I don't have any spare SATA3 mobo to test this same drive, but the controller seems absolutely fine, SSD works great and HDD still doesn't work even if I hook it up in the same port used for SSD.
This drive has the latest (and the only one available) firmware (CC32), I tested it with SeaTools and it passes all basic tests.
What could be the culprit? My best guess is that the drive controller itself treats interfaces differently using different pcb components, some of which are faulty, but it seems like a longshot.