You can change the User folder name by one of these methods:
https://www.tenforums.com/tutorials/89060-chang...
UEFI is the new replacement for BIOS. Read more about it here:
https://www.howtogeek.com/56958/htg-explains-ho...
https://www.marksei.com/bios-uefi-explained/
If you have performance issues you can go over this checklist to make sure the install is set up correctly, optimized for best performance, and any needed repairs get done:
http://answers.microsoft.com/en-us/windows/wiki...
Start with Step 4 to turn off Startup freeloaders which can conflict and cause issues, then Step 7 to check for infection the most thorough way, then step 10 to check for damaged System Files, and also Step 16 to test a new Local Admin account. Then continue with the other steps to go over your install most thoroughly.
Update your drivers from the PC or motherboard maker's Support Downloads web page, using the full model number, Serial Number or Dell Service Tag on sticker. Compare the latest drivers available for download with the ones presently installed in Device Manager reached by right clicking the Start Menu. Make sure you have the latest BIOS or UEFI firmware, Chipset, Display (Video), Sound, USB3, Bluetooth, Network and all other drivers, or else download and install the latest now.
Updating drivers from the Device Manager or Windows Update is rarely enough.
If you do all of this and it performs well enough then you don't need to do a Fresh Start, Reset or Clean Install. But if you want to try one I'd do the Fresh Start:
https://www.techrepublic.com/article/how-to-use...
I hope this helps. Feel free to ask back any questions and keep me posted. If you'll wait to rate whether my post helped you, I will keep working with you until it's resolved.
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