My son gave me his Dell Inspiron 400 to have a look at. The last time he used it it went into hibernation and now wont start at all. When you power up the PC the power lamp goes white then immmediately goes amber/yellow to indicate it is still in hibernation. There is nothing on any connected monitor (I have tried different monitors and connecting cables just in case) and it does not respond to keyboard or mouse. I even downloaded manual from Dell and removed the case, hard drive and CD/DVD drive to get at the bios battery and reset strap - I followed procedure in manual for reset but all this proved fruitless. Has anyone else struck this problem and found a solution. I haven't found the Dell site to be too much help.

These are very compact machines about 1/2 shoe box size and very awkward to work on.