Kinda like what chef said - burn at the rated 8x for your 8x TYs. 8x or 12x if you're using 16x media.
These days, with good discs and a good burner, there's no point in going as low as 2x. In some cases it can actually make the burns worse. Aramchek's linked post is well worth a read regarding that subject. :iagree: