Has anyone had a similar experience. I have a two month old PC with Vista Home Premium, 4096MBs of RAM and a Pentium Core 2 Duo E6600 processor, so plenty able to cope with Vista. I left the computer for a couple of hours. When I came back to it the monitor was on standby and I assume the PC was in sleep mode, but I could not ‘wake it up’ No response from the keyboard, or the mouse, and when I switched it off at the front of the tower, nothing, the fans still kept on whirring away. I had to switch it off, and then on again, at the mains. I have now set the Power Setting to High Performance so that the computer is not put into sleep mode, but I would like to be able to go back to the Power Saver option. This sounds as though it might be related to Hiwatts problem. Any ideas, anyone?