Digital BW, The Print

when I send to the printer (epson driver, best photo, abw) a 'too' big
grayscale tiff the printer will print only 2 thirds of the whole image.

I have tried only 2 of these big files, both times the file size was
configured at 1440ppi. 

I'm not sure the problem is the file size or the 1440ppi setting. For
one of these images I remember the file size was bigger than 300MB

anybody else having the same problem? I just wonder whether the
printer has somthing or is my win2k OS playing games.
  
thanks,
 Rodrigo