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I'm trying to install Funtoo/Gentoo on my desktop. I have the GPT partition table set up and I can boot the kernel. However I keep getting an error:

/dev/sdb3 is not a valid block device

I'm unable to get anything out of it. I'm at that point forced to hard boot my system.

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migrated from Aug 23 '11 at 18:52

This question came from our site for system and network administrators.

That's a quite poor question. You don't tell us where the error message comes from or what is happening at the time, what you mean by "can boot the kernel" (which seems to contradict your question title), or even what partitions/disks you have and why you expect there to be a /dev/sdb3 in the first place. – JdeBP Aug 24 '11 at 1:25

I think that booting to a GPT disk is only possible if the Motherboard supports UEFI. Booting from GPT lists a lot of details. Of course this may apply to Windows only which could make my answer unhelpful...

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That used to be true. It stopped being true earlier this year. – JdeBP Aug 24 '11 at 1:06

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