You´re welcome, but this puzzles me a bit too. I do repair laptops but never seen this behavior before. I would check: - The Memory with MEMtest, - Take out the battery and see if it helps, - Look if the ventilator is spinning up when pushing the start button, - Reseat the RAM, - BIOS reset/restore defaults, - Use a life-CD/DVD, Linux based so it´s legal and for free, - Backup the important data and reinstall Vista. That´s all you can do, flashing the BIOS isn´t an option in my eyes and if nothing helps than I have to point to the motherboard itself or the HDD and DVD-RW drive.