card reader no showing in My Compter

[scaniavabis]

There is a 4 slot card reader built into my Pc but it's not showing in "Computer" It used to label them as removable drives "E" to "H" as I recall.
It used to work fine but I don't use it much and now that I want it it's gone. If I put a card in one of the readers it doen't show or open the card file or anything else for that matter.
I've checked that all boxes ticked in "Start Up" when I run msconfig.
I've checked and there are no yellow question marks anywhere in the Device Manager.
I can't think of anything else to look for. The PC regularly checks for updates to both Microsoft and the manufacturer (HP) in this case. PC 1 year old, HP's best (business use) and an OS of Vista premium. WEI of 4.2 Any thoughts appreciated

[scaniavabis]

sorted thanks. turned out to be a desktop cradle for a mobile phone upsetting usb's. the phone charger part of the cradle was powering the pc through the usb port even when power cable from wall to the pc was removed. very odd!