Swapped hard drives in two (nearly) identical laptops and one won't boot

[G33kyG1rl]

I love my laptop so much I bought one for my son to use for school and light gaming with Minecraft. In all honesty it's too much laptop for him, but I got a great price. The one I bought has a few nicer features than my old one (a 3D screen and a Blu-ray drive) but otherwise they are identical machines. I wanted the nicer machine for myself because my son is just 11 so I swapped hard drives, thinking the drivers for a Blu-ray and a 3D screen wouldn't keep it from booting, and the old machine booted with the hard drive from the new machine in it, but the new machine (the one with the 3D screen) will not boot and won't go past the screen where it asks you to choose UEFI or Legacy boot. I'm not sure how to get past this, since even if I put the hard drive back in the old machine and downloaded the 3D driver, I'm not sure it would stick. I really don't want to have to wipe my hard drive. I mean, it's just a SSD and all my data is on the other hard drive, but I would like to avoid it if at all possible. I should probably also mention, the old machine was running 8.1, the new one 10, so when I swapped the drives, we're now running 10 in the old one and attempting to boot the newer machine in 8.1. Not sure if that makes a difference at all, just thought I would mention it. Does anyone have a suggestion for me to try to get this thing to boot?

 

[rgd1101]

MERGED QUESTION
Question from G33kyG1rl : "Swapped hard drives on what I thought was almost identical laptops..."

I bought my son an identical laptop to mine, or I thought it was identical. At least identical enough to where I thought it would boot and I could update drivers. Only differences that I could tell was the new one has a 3D screen and a Blu-ray player whereas the old one does not. New one came with Windows 10 and I would like to stick with Windows 8.1. The newer one is also in better shape than my old one, so when it got here I swapped the hard drives and his works just fine with the hard drive from the new laptop in it (that would be my old one laptop) The new one won't boot. Screen pops up asking if I want to choose UEFI or Legacy boot. This is Windows 8, so there is no option for F8 to check out drivers, etc. Anyone have any tips to get it going? I mean, I guess I could remove the hard drive, put it back into the old machine, try to download the other display driver and see if I can get it to stick, but I didn't think something as simple as a display driver would keep it from booting altogether.

 

[G33kyG1rl]

I didn't realize that first one posted. I tried to search for it, but couldn't find it, which is why I reposted it. My apologies. I desperately need to get this problem worked out ASAP. Really don't wanna wipe it but don't know of another option.