I have a HP540 laptop. The laptop works fine when it is in safe mode. However when it is switched on in normal mode, it works for a minute and then it gets switched off. I have removed unnecessary softwares by going into msconfig>startup. It did not helped. Tried to UPDATE the BIOS, but could not find the right version for my system. My correct BIOS version is F.02 released in 2008. I have alternatively formatted my complete laptop hard disk; But that has also not helped. Please help me. Suggest, what more can be done.