Can anyone tell me what AMD discrete graphics card best matches the performance of the integrated video of the new AMD Ryzen™ 7 5700G? I'm thinking of picking one up because of the lack of video cards, but if say an RX480 is better, then I won't bother.
From what I've read the GIGABYTE GeForce RTX 2080 seems to be the preferred choice.
I don't know the answer to your question about which video card best matches the integrated graphics of the AMD 5700G CPU, but I've found the integrated graphics does work well at 1080p on mid-level games like Serious Sam and things of this nature. My most recent build (Alien Vs. Predator Requiem Rebuild) is running with just the integrated graphics.
Ryzen 7 5700G is roughly equivalent to RX 550 performance.
You should definitely get "everything" better with a RX480/580, specially if you get a solid brand like ASUS RoG STRIX. If you have a good deal, why not.
But!
You might want to use the iGPU for a while more until the prices crash. The 6700XT is starting to appear with a 650€ price tag here in Portugal and a 6600XT is 480€
I play like dota2 only but if u have fast ram ryzen ready memory with minimum 16gb share virutal. And buy new cpu fan. U dont need more than 60-120 hz/fps. Dota2 works with manual graphic settings to 120+ but dont know what game u play. 90% is becuse game boosters windows services. Old bios update, wrong chipset drivers . When u ask like that u need what game u going to play , search game + 5700g fps in you tube and u see