Can't set RAM bus speed to 3200 mhz, Need Help!

I have a single stick 8 GB DDR4 G.Skill Trident Z RGB RAM, 3200 Bus and an Asrock AB350 Fatality gaming K4 board. My CPU is Ryzen 1400, not over-clocked. So earlier I was using an Asus Strix RX 470 GPU, and I was able to run my RAM at 3200 Bus speed using XMP setting from my BIOS, and it worked flawlessly. And my single stick RAM was placed in the A1 slot. I have latest BIOS P3.40.

Recently, I got a Gigabyte Aorus RX 570 and things went south, first of all my system went in a boot-loop it would turn on and off several times before finally booting. After changing various settings when I finally reset my motherboard BIOS the problem finally went away. So after the reset I tried to set my RAM bus speed back to 3200 using XMP 2.0, profile 1 and the boot-loop started happening again. It seems the maximum bus speed I can do now is 2666 mhz while the system is stable.

As an experiment I tried switching the RAM to the A2 slot as I read somewhere that apparently the A2 slot performs better for higher speed RAM sticks. Now here's the interesting part on the A2 slot the ram locks in at 3200 bus using XMP and the system doesn't boot-loop but the GPU performance takes a drastic hit for some reason. I can't even get 20 fps pn games like Overwatch, whereas before when the RAM was in the A1 slot running at 2666 bus I would get 100+ fps. Same results in Heaven benchmark as well.

Please give me your expert opinions and advice as to why this is happening after a simple GPU swap and what I can do to fix the issue. Thanks in advance :)