1.开机Fn > F2 > Exit > Boot OS > Other OS > Fn+F9 > Fn+F10
（这么做是为了切换到PE能运行的模式）

2.重启Fn+F2 > Boot > Boot Mode > Legacy Support > Boot Priority > Legacy First > Fn+F10

3.重启Fn+F12 > 选择U盘启动 > 进到Win8PE分区 > 安装Win7

4.重启Fn+F2 > Exit > Boot OS > Win7 OS > Fn+F9 > Fn+F10

5.重启Fn+F2 > Boot > Boot Mode > Legacy Support > Boot Priority > Legacy First > Fn+F10