I got this from PCbenchmark... minimum was all pass but recommended, I'm getting a fail on the gpu...

"windows iconWindows windows iconWindows Check icon PASS
Intel Core i7-4790 Intel Core i5-2300 Check icon PASS
NVIDIA GeForce GTX 780 NVIDIA GeForce GTX 750 Ti
View Required Upgrade
Close iconFAIL
Memory icon8 GB RAM Memory icon16 GB RAM Check icon PASS"

Now here's what makes me curious, the recommended requirement on the GPU may be for 4k support. I run all my games at 1920x1080 and always disable bloom. If Fallout 4 allows one to run at 1080 and disable bloom, think I'll still get video lag?

Bethesda-Games are CPU-heavy and poorly optimized.
My sugestion: Set your "Shadows" to Medium.
... or cap it via ini-file to "8.000 (between Medium and High).
It's easier with the "Fallout 4 Configuration Tool - By Bilago"
Under the tab "Performance" you'll find "Draw and Dir Distance" there. Set both to 8000.
Link: https://www.nexusmods.com/fallout4/mods/102

You can also use the mod "ShadowBoostFO4".
Link Mod: https://www.nexusmods.com/fallout4/mods/63482
Link F4SE: https://f4se.silverlock.org/
Link Address Library: https://www.nexusmods.com/fallout4/mods/47327

Otherwise you will get massive framedops in Boston.

I played Fallout 4 when it first came out on my GTX 970 at 1080p and then at 1440p. It was mostly around 40 fps at 1440p, but with some pretty severe lows in the 20s. For me, it was playable. I had most of the graphical settings cranked. When I got my GTX 1080 Ti I was able to play with the high res texture pack and mods at 4k. If you have a 4790 and a GTX 780 you shouldn't have trouble, as long as you don't expect to get 60 fps.

Speaking from experience when I say you need something stronger than a 750. You can get a used 1060 (6GB) for a decent price.

Not sure if the MOBO can run that card, they said it may not but its the one I wanted to begin with rather than what I ahve. So I'll look into it...

Oh boy GTX750ti! Well... do not expect too much.
You will run out of VRAM for sure.

Maybe it's time for an upgrade? I bought a used 1080ti for 200€ last month for a friend.

I played fallout 4 back when it came out. I was 15 and had a alienware laptop with a i7 - 4720mq and a gtx 700 something, I can't really remember the exact gpu but it was 700 series. I played it at max settings at 900p and don't remember any major frame drops it was awesome back in the day. That was the major reason i moved to pc because my xbox one s would crash everytime i played the game for more than an hour. You should definitely be able to run it dude.

Also as a note, there is a next gen update coming for the game soon so it might be even more demanding, probably not a bad idea to get an offline install of fallout 4 now before the update.

I test ran Fallout 4 GOTY (GOG release) with an Nvidia GT 1030 2GB lo-pro card. It ran smooth at 1280x720 medium settings. My regular GPU is an RTX 3050 8GB. i7 3770 (3.4GHz 4c8t), 16GB (2x8GB) DDR3 1600MHz RAM, 1TB SSD, Windows 10, and 1TB SSD Linux Mint 21.1. Footage of my GT1030 2GB test run. https://rumble.com/v3akvo6-fallout-4-gt-1030-2gb-test.html

Fallout 4 Gameplay (GTX 750 TI | i5-2400 | 8GB RAM)
https://www.youtube.com/watch?v=_j3CO3kpNvE

There's a site called Can You Run It. Google search it and check it out. You'll get your answer.

2 rigs ago I played it with a 760t, but i had a much ebtter CPu i7 9700 and 16GB RAM

BTW the required recommendations are NOT for 4k.
You need much newer hardware to even get close to that.

As for your configuration you can likely still play it but with all sliders set to minimum.