As you can see it easy to swap out the PSU and put a GPU in it. In the video below a you tuber is upgrading his Dell Inspiron 3847 mini tower PC. The best card possible under those considerations would be the GTX 1050 ti.

Dell Inspiron 3847 Desktop with Flagship Specs (Windows 7 Professional. Intel Pentium Processor G3220 (3M Cache, 3.0 GHz).Best Inspiron 3847 Specs Reviews in 2021. HD Audio w/ Waves MaxxAudio 4. I tried to restart it and while it would appear to go through a normal boot up it would not get past the Dell icon on the screen.There was no BSOD, no blinkiig or solid orange lights or any other indicator of what might be wrong.just wouldnt complete the boot process.DELL. Recently i had it on playing either Pandora or Spotify.i left it on for several hours and when i returned it was shut down. It has an Intel i5 processor, 1tb had drive and 12 gb of ram.

Since then when i start up the PC it still acts like it is going to start normally but doesnt get past the Dell icon on the desktop. I connected the monitor to a laptop i have and it worked fine.By now i NO LONGER CAN ACCESS EITHER THE BIOS OR DIAGNOSTICS VIA F2 or F12. I tested the Monitor by hooking it to one of my cable tvs and it worked fine. I connected the monitor and pc with an HDMI cable.didnt work.