hi i got the x1150 all in one and to be honest i will never buy lexmark again. i had exactly the same problem when i bought compatibles so thought thats what you get for being cheap so went and paid full whack for lexmark own and they lasted approx two weeks and dried out on me. mine shuts down with pc too so got no explanation other than they rubbish.
i keep it for scanning and have since bought a epson r220 which i use for photo printing and wouldn't hesitate to recommend it to anyone its just brilliant at its job.