Please help, I still want the PC to be able to handle modern games on high and medium graphics.
I would change your CPU to this http://www.microcenter.com/product/428114/FX_4130_Black_Edition_38-39_GHZ_Quad-Core_Tray_CPU
because that APU is going to hold back the power of your graphics card.
And then you should be able to lower the rest of the price by finding a sub 50$ AM3+ motherboard.
Don't forget a cooler if you go that route.