Windows 8.1 Pro x64 UEFI very slow boot and shutdown

I appreciate your effort! However, my version is 9.5.15.1730 and I still have about a minute boot. Shuts down fine, though...

I have the same problem with a new ASUS X550LA laptop with an i7-4500 cpu and 8GB RAM that came with windows 8.  I upgraded it to 8.1 and my new laptop now runs slower than my old HP Zv6000 with 1 GB RAM.

Further, when I upgraded from 8 to 8.1, the upgrade process wiped out (or, at least, refused to recognize my local account) so I had to create another cloud-based account (which I don't want) and then I had to jump through the hoops (again) to recreate my local account.  Isn't interesting that the install/setup process can't recognize an existing local account when it does an upgrade from 8 to 8.1, but it has no problem recognizing the "lost" local user account (e.g., Joe) when I asked it to delete the new account with the same name (i.e. Joe) after I found both the new account and the old account in C:\Users.  Yep, it deleted both C:\Users\Joe and C:\Users\Joe_000) which, obviously, made it impossible to reconnect to my original lost account and configuration settings.  Even if Microsoft has a way to reconnect to existing accounts on an upgrade, wouldn't you think that after 20+ years of doing updates that they could figure out how to do it right and not force their customers to spend endless hours redoing and relearning the "new and improved" way of doing things?

I have the same problem with a new ASUS X550LA laptop with an i7-4500 cpu and 8GB RAM that came with windows 8.  I upgraded it to 8.1 and my new laptop now runs slower than my old HP Zv6000 with 1 GB RAM.

Further, when I upgraded from 8 to 8.1, the upgrade process wiped out (or, at least, refused to recognize my local account) so I had to create another cloud-based account (which I don't want) and then I had to jump through the hoops (again) to recreate my local account.  Isn't interesting that the install/setup process can't recognize an existing local account when it does an upgrade from 8 to 8.1, but it has no problem recognizing the "lost" local user account (e.g., Joe) when I asked it to delete the new account with the same name (i.e. Joe) after I found both the new account and the old account in C:\Users.  Yep, it deleted both C:\Users\Joe and C:\Users\Joe_000) which, obviously, made it impossible to reconnect to my original lost account and configuration settings.  Even if Microsoft has a way to reconnect to existing accounts on an upgrade, wouldn't you think that after 20+ years of doing updates that they could figure out how to do it right and not force their customers to spend endless hours redoing and relearning the "new and improved" way of doing things?

I did the 8 to 8.1 upgrade on an ASUS laptop and did not need to do a cloud account, just told the software I wanted a local account. It is not obvious that you can do this but fortunately I knew ahead of time that you could. Several places around the internet describe how to do this.

Thank you.

As for your problem, I agree with "rangerat" that there might be other drivers installed in your machine that are currently not compatible with Windows 8.1

You might want to try to check on the drivers yourself, although that might take some time ( consumed a whole day to find the issue - even called in sick to work on that day haha ( I just cant get that problem out of my mind )

Apologies if I wasn't able to help out.

Hi. My mobo has two Broadcom ethernet. I have solved the problem myself removing the updated driver of Ethernet: using the integrated driver of Windows the speed is good!

I think that temporarly you can try to remove or disable lan driver or disable the ethernet from BIOS.

If the slowest time disappear then it's possible to test with other LAN driver.

Note: in other cases the problem could be the Ethernet Bridge of Windows if enabled: removing and restoring can help to solve the problem.