My machine was working fine until this Thursday. I turned it on as usual but it wouild not load Windows. I am not very PC tec minded but reasonable practical. when I turn on the PC it runs through the BIOS screen then displays the options to start window normally - Safe mode - Using the last best known configurations. I have tried all these options but it just recycles through the the same screens again. I have read a number of other similar postings, and tried cleaning the dust, removing and replacing the RAM, using only on RAM chip, but the problem has persisted. Anyone got any ideas, all would be most gratefully recieved.