yeah, i've done it before. before it's installed, under device manager > computer, it'll say "standard pc"... then go into bios and turn on acpi and once windows loads back up, a series of devices will be found and installed, if i remember correctly. might have to restart. also, if you have a via chipset, it'd be wise to reinstall the latest 4in1 drivers for good measure.
in other words, should be no big deal. 🙂