A really good gaming build for under $600. It plays all of the competitive e-sports games at 200fps, and AAA titles are almost maxed out at 60fps+. The Rzyen 3400G is a great pick for gaming, it is on par with the 2600 and slightly behind on the 2600x. It might struggle with streaming and gaming at the same time. If you want to stream, upgrade to the Ryzen 3600. The build could get even cheaper by getting a cheaper case or switching to the Ryzen 3200G, or switching to a RX570 or RX580, but this particular parts list is really appealing. The manual pricing for the CPU, GPU and motherboard are normal pricing at Microcenter. Motherboard was an additional $20 cheaper from buying CPU and motherboard combo. Stock cooler works fine if you are not overclocking. This motherboard isn't really meant for OC'ing anyways, but you can do it at your own risk at burning out the VRMs.
I believe the 3400G is great 4-core 8-thread CPU that is oriented to home office and gaming tasks. Have not tried streaming, but the Ryzen Software has some nice built in streaming/capture settings built in. The RX590 is probably the best value since the 5500XT and 5500 came out, I've seen the RX590 pricing drop quite a bit. The 5500 and 5500XT require PCIe 4.0 for the best results, and they are still beaten by the RX590 on PCIe 3.0.
430W PSU is more than enough for this build.
The m.2 NVMe is wicked fast on this computer. At 500GBs I feel that its the best balance between a 1TB HDD for storage and a SSD for speed. 500GB goes a decent way for holding a number of games, but uninstall old games you don't play anymore, and storage space shouldn't be to big of an issue. Upgrade to a 1Tb if you need the space, and have the extra $50.
Overall, I think this is an excellent value build for those tight on money. I will try to build another system that costs even less.
Some tips. Cable management is rather difficult. A modular power supply would make it easier, but it does add to the build cost. Zip ties are your friends. I was able to get all the cabling on the backside of the case, and was able to hide the SATA power cords in the HDD tray, as they are unused in this build.