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On my laptop keyboard all Fn + key are labeled in blue. However Fn + X is not labeled and Fn + A - Z (other then X) prints out that letter. Its not printing X so what might it be doing?

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What make / model of laptop? They tend to have thier own setups with regards to keyboard. – DMA57361 Aug 19 '10 at 17:27
up vote 2 down vote accepted

Fn+X is used by a few vendors as a Diagnostic mode. It's meant to be used during boot only to get in and out of diagnostic mode. Otherwise does nothing.

Dell is one vendor I remember specifically using this combination.

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This is a dell. That sounds right. How do i get into diagnostic mode? From a simple google it seems i need to use the dell CD or HD (xp only?) if i havent nuked them to have a XP/7 partition – acidzombie24 Jul 10 '11 at 18:41
I don't own a Dell anymore. Been a long time. But assuming Fn+X doesn't get you into system diagnostic mode during boot, it will be used instead solely to get you out of it, when you are forced into diagnostic mode during a failed boot. And you are right, of course. Because this Fn combo is mapped, you don't get a X when used during normal operation. These combos are hardwired into the system. – A Dwarf Jul 10 '11 at 20:49

If Fn[a-z^x] works but Fnx doesn't, it might just be a problem with the keyboard. (Ie: pressing Fn stops the keybord from noticing when x is pressed.) It wouldnt be nearly the stangest bug i've heard of.

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what would be stranger :p thats pretty darn strange to me – acidzombie24 Jul 10 '11 at 18:27
Magic, for one. – David X Jul 10 '11 at 20:14

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