It seems there is a little bit of a misconception regarding the overclocking of a Dreamcast and VMU. All of the information I could find online states that the VMU *HAS* to be overclocked by the same ratio as the Dreamcast (200mhz -> 240mhz = 20%; VMU 6mhz -> 7.2mhz = 20%). I've tested with multiple VMU's now using different speed rating Xtal's (7.2mhz, 8mhz, 8.5mhz, 9mhz) and they all work 100% with the system overclocked to 240mhz or at stock speeds. This means the VMU only needs to be the same or faster than your specifc overclock. Peace.