Question Computer under-performing after upgrade

[LaminatedJoe]

I recently replaced my gtx 770 2gb with a gtx 970 4gb under the assumption it would provide a much needed performance boost, however i have noticed that it has actually made my computer perform much much worse. FPS has dropped 100+ in some games compared to the gtx 770 and im completely puzzled as to why.
I've already updated the drivers, removed and cleaned out the pciex16 slot and still the performance is dreadful.
If anyone has any ideas im open to suggestions.

Build:
i3-9100f
gtx 970 4gb, formally a gtx 770 2gb
16gb of generic Samsung ddr4
Z390 gaming x motherboard
2tb blue western digital HDD
256gb sandisk ssd which the computer is booting from
1000w cooler master PSU

 

[rgd1101]

what game?
check cpu/gpu temp and usage during the game?

 

[LaminatedJoe]

GtaIV over the span of about 30 minutes.
GPU never went above 70 degrees and CPU stayed at 45-50 the whole time.
GPU usage fluctuated between 50% and 75% and CPU was at 40%-50%.
Graphics all set to very high which is as high as they go.

FPS was between 40-60 most of the time with a few short lag spikes during explosions and such that brought it down to 10 fps momentarily.


Also with minecraft i was getting 150-200 fps in minecraft with extreme shaders which dropped to 90-110 fps after upgrading to gtx 970.