On boot up my computer sometimes shows a variant desktop, i.e. plain grey and faded text. On reboot my normal desktop is displayed, but sometimes I need to reboot more than once and on the final reboot I see message: "One of your disks needs to be checked for consistency". Following the check the display appears as normal without the problem. First time this happened I sent my computer in for investigation, but when the technician booted it was okay (of course!). I obviously don't want to pay for a check every time this happens - is there any other line of exploration I can take?