I should start by saying I am no expert although I can find my way around my computer reasonably well and understand enough to get by. For me, I paid for a downloaded upgrade from t Windows 7. I went through the hoops with Microsoft compatibility test and to all intents and purposes my PC passed. The download went smoothly enough and Windows 8 booted up seemingly normally. However, it was pretty obvious that my graphics capability was not up to standard (although Microsoft said it was) and search as I may I could not find a windows 8 compatible upgrade for my particular machine.Things went downhill after that and I finished up doing a clean re-instal of my Windows 7. Would now not touch it with a barge pole!