Yes, set the main SATA controller to AHCI mode, although this will have no effect on the Windows 7 install you plan. I just like it that way.
Then go in and change the Marvell Controller to AHCI, before you install Windows 7.
I've never installed an OS in this way. Please post back and let us know how that works

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Speedfan says my temps are 42C for processor, 56C for each core, and 46C for the system.
You should always apply a very thin coat of paste to the heatsink when you install it. But the stuff on the tab on the bottom of the stock heatsink is fine. It's not going to make a 10C difference.