updated the bios via service tag so it is a dell tablet.... so I guess windows 8 and 10 are the only OS this thing will accept even though they are way newer than the machine.... I don't have a restore disk... that might work if I had one.... i'm ready to throw this thing out the window... windows 8 and 10 work and installs just fine but they peg the cpu at 100% usage, 100% of the time so it's always lagging to the max on max performance.... it has a 1.5 Ghz Atom single core without hyperthreading and without turbo boost btw.... I can't install the os that came with it from the factory since I need the restore disk I don't have... the retail copy of vista just blue screens after loading... can't install windows 7 as it also after loading setup, blue screens can't downgrade to xp it blue screens after loading setup this thing is just screwed