I turned my pc on one day to find auto detecting pri master (not detected) auto detecting slave master (not detected)
It then gave me an option to start up via boot disk.
After a couple of tries, the monitor will now not turn on and I can't do anything with it!!!!
The monitor works ok on another PC. I have changed the CMOS battery and put the HDD in another PC where it performs POST ok, but does not load fully (I suspect it is because they're very different in age!!!
Often had this problem - Rayuk's suggestion makes good sense, also try simply removing the eide cable and reinsert it, plus remove the power connector and reinsert that. For some reason (perhaps wear and tear) the cables do not always make a perfect connection.