I have also noticed a very odd problem. Actually, this has happened long time ago, but happened very briefly to be noticed.

When I use the Snow Leopard now (recently did a fresh install), the access to the SATA drives seems to hang (Write / Read are both at 0 speed) while the HDD indicator is fully on and during that time, anything that requires disk access will hang until several seconds (like 15 seconds or more) has passed.
This had really been driving me nuts. Has anyone experienced this, and how did they fix it?

I have attempted to use these PATA related Kexts and switched the SATA to "Compatible" mode, but none of kexts worked; I always got a hanging system waiting for the root device. And even Windows 7 will not be able to boot either.
In the past years, I have read somewhere, that there is a strange bug in nForce which causes this same exact hang-up if the nVidia Graphics card is engaged and so is the AHCI. And I thought if I switched to "compatible" mode, it will be acting more towards classic IDE mode (which it really does), but then I can't get anything to work in this mode.

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