Your video card is at the bear minimum for 4K, upgrading that first might make more sense. My old PC when I upgraded from a 1030 to a 1050ti solved most of my playback issues. I have upgraded the PC since to a AMD Ryzen 7 3500 (last years cpu), new mother board and 16GB DDR4 3200 memory for under $200 on black Friday but honestly it made very little difference in playback performance compared to the GPU upgrade. Even a 1050ti is getting a little dated as something a little higher up the scale is highly recommended. A lot of these older GTX cards are flooding the used market as many are upgrading to the RTX line.
"Smart enough to know better, to old to care" ------ Dedicated Bat Cave Home Theater, JVC RS49U/Mitsubishi HC7900DW Projector, 110" 16:9 Jamestown screen with variable power masking for CIW 2.50:1 to 16:9, Marantz 7009 with 7.1.4 Atmos with Ohm mains,3 DIY Subs (2 15" (1 ported, 1 sealed and a 12" 4th order bandpass), 1 DIY butt kicker, Custom Built HTPC, 18TB DroboFS NAS