I have a p4p800 motherboard and my sata drive is hooked
up to it with windows installed. I also have a IDE harddrive
hooked up with suse 8.2 on it. Is there a way i could compile
a kernel for SATA support then load it onto the SATA drive?
What chipset controls the SATA on my motherboard?

SATA drive can be set in the BIOS to compatible or enhanced mode. In compatible mode your old kernel and linux installation process should work fine, although you may not be able to boot MSWin (assuming that was installed in enhanced mode).

If you then install a SATA enabled kernel you can switch the BIOS back to enhanced mode. However your drive will move from /dev/hda to /dev/hde, so you would need to edit the entries in /etc/fstab to reflect the change.

You could do this while booted from a rescue disk or CDROM, but it is probably also OK to edit fstab, reboot to BIOS, change SATA mode, then reboot to linux. If you have a rescue disk it is easy to undo the changes if it turns out the kernel can't handle enhanced mode.

NB Recent Knoppix live CD can handle the SATA drive on my P4P800-VM m/b, and is a harmless way to experiment.