ASRock, the new A520 motherboards are a valid alternative to the B550
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A520 is the entry-level chipset of the 500 series from AMD and it does not offer overclocking support. It is reasonable to assume that the A520 lacks the PCI Express 4.0 interface, although AMD has not officially confirmed this.
VideoCardz has revealed the details of two of ASRock's A520 motherboards: A520M-ITX / ac (mini -ITX) and A520M Pro4 (microATX).
ASRock A520M-ITX / ac
Credit: VideoCardz The similarity of the A520M-ITX / ac to the current B550M-ITX / ac it's really impressive. If it weren't for the model name on the PCB, you could swear you're looking at the B550M-ITX / ac. The A520M-ITX / ac appears to be equipped with an eight-phase power subsystem, a configuration commonly found on cheaper B550 motherboards. As expected from the mini-ITX form factor, the motherboard only has two DDR4 memory slots, but memory overclocking should be good enough given the short lines to the processor.The motherboard it can accommodate up to five storage devices. There are four SATA III connectors and a single M.2 slot on the front. The A520M-ITX / ac also has only one PCIe x16 slot. From a connectivity point of view, the A520M-ITX / ac is a spitting copy of the B550M-ITX / ac. The rear panel offers a DisplayPort and an HDMI port, while for the Internet connection there is an Ethernet port and a wireless network card.