If video card to my motherboard?

Want to take rx550
Motherboard m5a78l - m lx v2
Percents - athlon x2 250 (will change to NG on fx6300)
PSU - 400W
This EU co - https://www.citilink.ru/catalog/computers_and_notebooks/parts/videocards/469839/
If she will go to my mother?
Just last its download to 100% and 70-80 percent loaded (in GTA 5 for example)
Or better gt1030 to take?
And again, what cooler will fit fx6100? So I butt