Lower frame rates and FPS drops after upgrading monitor?

[seejaydotexe]

Happy Holidays!
My brother recently upgraded his monitor from a 2004 monitor to a ViewSonic VX2457-MHD 24" inch monitor. Previously, he was playing Overwatch at 70fps minimum and never dropping below. He is still playing at 70 but there are random drops in framerate. Even older games like Borderlands 2 don't even get 45 FPS at the lowest settings.

We recently moved all of his parts to a new case (Phantek P400) because the old one was getting cramped and had poor airflow. We looked for new drivers and tried to change the display settings.

Here are the parts for his build:

(We built it from this video minus the harddrive and case): https://www.youtube.com/watch?v=O_15dUbpaOA)

FX-8320 CPU: http://goo.gl/NRYIsJ
MSI 760GMA-P34: http://goo.gl/K6UtCX
Crucial Ballistix 8GB (4x2): http://goo.gl/hQ5acw
Western Digital 1TB Hard Drive
Sapphire R9 270X: http://goo.gl/qKnQFF
EVGA 500W Bronze PSU: http://goo.gl/mQVJ5p

Any help is greatly appreciated as him and I are extremely frustrated that this isn't working right.

 

[Emelth]

What resolution was your old 2004 monitor? I'm guessing the resolution of that monitor was less than 1080p which is the reason your FPS has decreased.