http://winsupersite.com/windows-8/windows-81-update-1-review
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There was some confusion during the beta about why certain PCs have this button and some do not. But here's the answer: Its appearance is keyed to an internal setting called the Power Platform Role that PC and device makers must set accurately in order to obtain the Windows logo. If this setting is configured as "Slate," the button will not appear, because it would be too easy to tap accidentally and tablet users are comfortable with the edge-based UIs. If it is set to "mobile device," as a laptop or Ultrabook would be, the button will appear.
In other words, it has nothing to do with the availability of features like multi-touch or Connected Standby.
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基本上電腦廠商在電腦上有個 Power Platform Role 內部設定。若設定為 slate,這個電源圖示就不會出現。若是設為 mobile device,像是 laptop 或 ultrabook,這電源圖示才會出現。


























































































