4. Warranty Exclusions (b) Microsoft is not responsible and this warranty does not apply if Your Microsoft Hardware is used with an operating system other than the Windows operating system preinstalled in Your Microsoft Hardware, or any contemporaneous or later version of that operating system.
國外其他使用者的解讀(也有人去Answer Desk問)是 原始,或是從 Recovery Partition裡倒回的 Windows 的算 "preinstalled operation system",但如果幹掉+用其他方式裝,有被判保固無效的風險。總之條款裡並沒有明著擋你裝dual OS就是了,但是要小心Windows 這邊如果搞掛系統, Microsoft 可能不會協助(軟體/作業系統端)
裡頭Microsoft相關人員的發言如下 (這是之前的SP2時的文章,所以裡頭提到的是Windows 8 Pro) Yes, you can dual boot the Surface. Microsoft will not assist in the setup or configuration of the Dual boot. The warranty gives you 90 days of Technical support for the Windows 8 image that we have provided on the Surface (preinstalled software). However, should something happen to the Surface to physically damage it (eg cracked screen, paint chips, dents, etc), you can still have your Surface repaired.