I rarely use the HP Photosmart C6250 printer/copier/scanner connected to my Vista PC. Moreover, if it is turned on when I boot the PC, Vista locks up. So, the Photosmart is usually turned off and stays that way until I need it. This has worked out ok for the past couple of months.
However, something happened after this week's monthly Microsoft Patch Tuesday. If the printer is off, the HP Digital Imaging Monitor uses nearly all CPU resources if the printer is not turned on. This brings the PC to a near grinding halt. I'm not sure what the specific cause is. But, this definitely started happening only have the Patch Tuesday updates were installed.
Yet another reason I am never buying another HP printer.