How unusual is this? I bought a brand new Sega Sports Dreamcast on eBay 2 week ago. I couldn’t resist! The thing looks so cool in black and getting a new one brings me back. But what’s really surprising is after 5 full days of being powered off it still retains the date and time. I am in total shock! This model is from August 2000. How long do these battery’s usually last before they stop keeping a charge and need replacement? Doesn’t anyone here still have a Dreamcast with an original battery that still works?