Sorry I'm late in getting back to all of you. Here are the paticulars: I had an HP Pavilion a814x with XP Home installed. When I tried to upgrade the memory I suddenly could no longer power the HP back up. The power indicator blinked green vice a steady green. I reconfigered back to original mem config, but still had same problem. I pulled the power supply out and it would show a steady green lite with power supply. I thought that it could be on/off switch or possibly I damaged the motherboard installing the SIMMs. I had the Vista machine recently purchased, so I removed the hard drive from the HP machine and mounted it in the Vista machine. I can access the HP drive and see most of what was out there, but have been unable to access most recent photos and some files that were bookmarked and stored. That is where I'm at, being able to access some data and files, but not all. I think that this a slaved drive already. The Vista OS is the boot drive. I just can't get through my brain what I'm missing about the inter relation between the two OSs, why some data is readily available but other data is not.