Windows 10: my dell office computer wont post after i changed it from legacy to uefi

it said before i swapped it msg: hard drive - hard drive not detected

:)

 

Legacy v UEFI - Dell E6420 BIOS

Hi There the Dell E6420 Laptop I have is at the Legacy not UEFI set up. I have read that by resetting it to UEFI I might be able to increase the HDD capacity to 2TB. However, I would like to know how this would affect the machine in booting and performance.
When I changed it to UEFI to see, I found the boot sequences that were ticked for Legacy were grayed out as if no more applicable.

So, please advise what are the pros & cons if changed to UEFI and if that is necessary at all. The machine as of now, is working fine. Thanks.

 

Return to Legacy from UEFI - BIOS

Hi There

A while ago I was helped here to change from Legacy to UEFI. However, since then it seems, the Laptop (Latutide E6420) is running a bit slowly which was otherwise very quick until then. Now, it takes nearly a minute or so to boot up or shut down or even
to close a file. Just a couple of days ago, I updated the latest BIOS for this machine recommended by Dell.

I tried to go back to Legacy but the system was asking me to reset to UEFI or face boot problems. One advise said that I could disable 'Secure Boot' in Boot Manager and reset to Legacy. However, the Boot Manager is listed under UEFI Boot process and it only
starts Windows. Is there any way as easy as I changed it? This is absolutely under the hope that all will be as normal as it was in the beginning. Please give your thoughts and advice. Thanks.

 

Legacy to UEFI

I'm debating moving to UEFI form my now legacy BIOS (Award Software Int.) the mother board is a GA-Z68XP-UD3 rev1.0 on the the following link it shows a UEFI BIOS U1J )UEFI BIOS)

https://www.gigabyte.com/Motherboard/GA-Z68XP-UD3-rev-10#support-dl-bios

Currently I'm running the legacy F10 BIOS. Does installing the UEFI BIOS automatically take care of everything to get to the UEFI BIOS? Installing the UEFI BIOS following the instructions using the Q-flash method GIGABYTE How to Reflash Motherboard BIOS

What's steps do I take and in what order?

Much appreciated