Installed New CPU & Motherboard and Games Run Worse

[Rubberguy1]

I just got my new setup up and running with some hand me downs from my friend who just recently upgraded. I have installed games like GTA V and Farcry 3 and have been having major issues. My old motherboard and processor ran these games pretty bad but at least kept the framerate consistent. With my new setup the max framerate I get is around 40 in Farcry and GTA but will drop and go up to 60 and back down CONSTANTLY. I don't know why and it's starting to get irritating.

My new specs are:
GTX 760
FX-4300 3.8 GHz
8 GB RAM
760GM P34 MSI

any help would be great. Thanks

 

[toot12311]

those specs are low end... not really anything else to say

 

[barto]

What were the spec for your old setup?

 

[Rubberguy1]

What were the spec for your old setup?

I changed the motherboard and processor so I had A8-3800 APU 2.4 GHz Quad core but can't figure out the specific motherboard, sorry.