I have a Hp C5180 Photosmart printer  and have noticed the same problem. 
When I first bought it the yellow ink cartridge went pretty fast and I 
called HP up and they said it must have come with a starter cartridge. 
Well to make a long story short I insisted on a new cartridge. I started 
making out a log of the usage and when I have to replace a cartridge. 
Well it seems real suspicious ,like Dean Kurkal said,  that one uses the 
"black " ink option and it keeps using colored inks up. I think I have 
proof now (with the log). Just wanted everyone to know Dean is not the 
only one who has problems with HP Photosmart printers. Maybe others can 
e-mail if they also have a problem,  this way we can document this with HP.


Russell

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