Did you carry on using computer as is for new Steam account? As I suppose there's always a chance what got you banned originally has left some legacy behind even after uninstalling.
May be do a format when you decide on which graphics card you are going with, to remove potential future issues if you try Steam for a third time.
May be do a format when you decide on which graphics card you are going with, to remove potential future issues if you try Steam for a third time.