Although focus will be on the new Ryzen CPUs with updated architecture, that’s only one half of the picture when it comes to assessing AMD’s new platform. Complementing the CPUs release are a new series of motherboard chipsets, catering to enthusiast, gaming and entry-level segments. Plus, unlike Intel’s 200-series motherboard platform, AMD have kept their 300-series platform quite simple.
The first notable fact is that the AM4 socket is supported throughout the CPU and motherboard range – there’s no high-end exclusive analogue to Intel’s X99/LGA 2011. This will make piecemeal upgrades much simpler (and hopefully cheaper) in the long-run; for instance you could purchase an X370 motherboard and Ryzen 3 processer, and then upgrade to a high performance Ryzen 7 1800X later solely by replacing the CPU.
Another budgetary consideration is that all Ryzen CPUs are fully unlocked; instead overclocking is limited on a motherboard chipset basis with both X370 and B350 lines capable of pushing the CPU beyond spec. Budget overclockers will therefore be eagerly anticipating the release of Ryzen 3 and 5 CPUs, and in the long run will be better served by AMD’s lineup if overclocking is important to them.
At the top of the ladder sits X370, designated as the enthusiast chipset. The key differentiating factor between it and B350 is multi-GPU support, bifurcating the 16 PCI-E 3.0 lanes to dual 8x configurations. Both NVIDIA and AMD have de-emphasised multi-GPU graphics recently and very few consumers opt for these configurations due to cost, so the delineation makes a lot of sense; it may however dampen the enthusiasm of those who slot-in second GPUs late in that model’s life cycle.
Stepping down to B350 also limits I/O support, reducing the number of native USB 3.1 Gen1 ports to only six (but retaining six USB 3.1 Gen2 ports) and SATA 3 6Gbps ports to four. That’s no great hardship however, and may be offset by additional functionality added by board manufacturers. Overclocking support and high-performance GPU possibilities afford the B350 the label of 'performance chipset' below X370.
The mainstream section of the market is catered to by the A320 chipset. It’s only at this point that overclocking is restricted, and other I/O options are also shaved off compared to the higher-end models. Full x16 PCI-E 3.0 graphics are still an option however, as is NVMe storage (although board manufacturers may well not include this feature depending on cost).
Additionally, AMD have created two small form factor chipsets specifically for the AM4 platform – the X300 and A300. We’ll got into more depth when these chipsets are released, but the chief take-away point is that the X300 is an overclocking-capable chipset that is physically very small, allowing for far more flexibility in motherboard design than typical desktop platforms.
In recent months CPU cooler manufacturers have been falling over themselves to announce support for the new AM4 socket, but little information has been released regarding the differences between AM3 and AM4. As it turns out, the differences are quite small.
Firstly, the classic ‘clip-on’ cooler mount will continue to be supported on AM4 at the same specs as AM3. That will reduce the cost for many users towards the budget end of the spectrum, and has hastened support for low TDP coolers.
The chief difference between AM3 and AM4 is in the bolt-through cooler mounts often used with high-performance coolers. The hole positions for AM4 are offset from those for AM3, requiring a new mounting mechanism and backplate in many cases. Some motherboard manufacturers are supporting both AM3 and AM4 bolt-through holes in their designs – such as the ASUS ROG Crosshair VI – but this should not be assumed to be true in all cases.
All in all AM4 appears tailored to be minimally disruptive to both users and cooler manufacturers, whilst providing a good basis for the platform going into future generations.
An Eye on the Future – APU Support Built In
It will be apparent when the full range of motherboards are released that APUs are support, despite Ryzen 7’s not being equipped with integrated/on-die graphics components. This is because AMD wanted to ensure full support for AM4 Ryzen APUs when they become available later in the year, and not restrict them on a per-model or per-chipset basis.