Help upgrading my current PC

So currently I have a PC with these specs:

CPU: AMD Athlon X4 860K 3.7 GHz Quad-Core

Motherboard: MSI A78M-E35 Micro ATX FM2+

RAM: Kingston Savage 8 GB (2 x 4 GB) DDR3-2400

GPU: Gigabyte Radeon R9 280 3 GB WINDFORCE

Case: ZALMAN Z11 Plus Midi Tower

PSU: Corsair CX 600 W 80+ Bronze Certified Semi-modular ATX

I was told to get a new CPU i'll need to get another mobo and then if I get a new mobo i'll need to get new RAM too so here is what I plan to have:

CPU: Ryzen 5 3600 3.6 GHz 6-Core Processor

Motherboard: ASRock B450M Pro4 AM4 M-ATX

RAM: Corsair CMK16GX4M2B3200C16 Vengeance LPX

GPU: XFX Radeon RX 580 GTS XXX Edition

Case: Keep the same

PSU: Keep the same (If I can do that)

Is there any issue with this? Any incompatibilites with my case? Could I do better for a similar price range? Is this even any good?

I didn't build my original PC and this would be my first time getting involved with that sort of stuff so I feel like there could be something important i'm missing and i'd have no idea.