well here goes...
1) dl LogoX (get the gui version, MUCH easier to use)
2) using photoshop (or paint), make a GRAYSCALE image 100 x 17 pixels. it can be anything u want. save it as
RAW or
BMP3) run LogoX
4) click browse under the xbe file box and find your dashboard
5) click browse under BMP/RAW file insert
6) under function, choose
insert boot logo7) click apply

upload and you're all done