Just curious! Im predicting that if you leave the PSP alone when its on the XMB at 222mhz it would last about 10 hours. 222/1=222.
So 10 hours X 222= 2220 hours.
Thats a long time if im correct! Probably even longer right?!?! But yeah at 1mhz its gonna be almost equivelant to not being on at all!