Windows 7 - Acer 5315 sata xp

Have a ACER 5315 Notebook with an 80 gig HDD that is nearly full. Bought a 320gb Samsung SP SATA and installed it in the ACER. I forgot XP lacks SATA drivers. I want to skip the slipstream bulls..t and get this going using the KISS priciple (Keep it simple stupid). I'm just putting XP SP3 on it to allow me to use my last Windows 7 upgrade license.
I'm going to turn off SATA (Native) and use IDE to work around the BSOD and allow XP to see the HDD. My big question is:
Can I go back to SATA and it's enhanced feature set "after" I fully install Windows 7 and reboot into BIOS and turn SATA (Native) back on?
Windows 7 should have the ACER drivers? I will load the ones from ACER onto the Windows 7 install after the installation is complete and then reboot.
I assume Windows 7 will find the drivers and see the SATA correctly?

No need to install Win XP, do clean install with are Upgrade DVD.

Clean Install with a Upgrade Windows 7 Version

Tried Windows 7 clean install without XP. It went through the motions and did not see the HDD. Bios sees it and the splash screen sees it. The drive is an unformatted bare drive. Why Windows 7 does not see it is wierd? I will turn off SATA "Native" and see if Windows 7 or XP sees the HDD. If so I will load it then go into Bios and re-enable SATA and boot. If not I will plug it into a USB 2.0 adaptor and see if it even works?
windows 7 should have the SATA drivers.

Do you have the sata drivers, if yes try this:

SATA Driver - Load in Windows 7 or Vista Setup