I also notice that from time to time that the bios takes a bit longer to complete the post cycle and that 10 on my desktop doesn't complete the windows load as quickly as 8.1 did. On my laptop 10 is super fast, even faster than 7 or 8.1 were but it doesn't have a uefi bios. When I was on bios 2702 I had several instances where the bios seemed to hang after I'd completely shut the power off to the board. Have you checked your bios settings to make sure that fast boot is still enabled? Also make sure that turbo mode is enabled during post which also speeds things up a little bit.
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