I'm currently using a gaming laptop with an RTX 3050 6GB and 16GB of DDR5-4800 memory, but I'm saving for a desktop. I originally planned to build on AM5, but I'm now considering an AM4 system with a Ryzen 7 5800XT, Radeon RX 9070 XT, and MSI B550-A PRO motherboard. I found a good deal on 64GB of DDR4-3600 CL18 memory using four 16GB sticks, which costs less than 32GB of DDR5-6000 CL32 for an AM5 build. Would the B550 motherboard run four sticks reliably, and is 4×16GB a good choice? I'm mainly playing games such as Icarus, Scrap Mechanic, Grounded, Minecraft Java and Bedrock, and other open-world titles at 1440p on high settings. I also host worlds for three or more players, so I'm wondering whether 64GB would be useful or simply overkill. The AM4 build with 64GB is cheaper overall.
3 Answers
If you’re building from scratch, AM5 is the better long-term platform. A Ryzen 5 7500F or similar CPU with 32GB of DDR5-6000 should handle 1440p gaming very well, and you’ll have a much better upgrade path later. AM4 only makes more sense if the motherboard, CPU, and memory are substantially cheaper, such as through a used bundle.
That 64GB kit is not automatically a bad deal. You could install all four sticks, or use only two 16GB modules and sell the other pair if you don’t need the capacity. The extra RAM won’t substantially increase gaming FPS, but it can help with game hosting, heavily modded Minecraft, multitasking, and future use. Just make sure the memory is a matched kit and test stability after enabling the rated profile.
The B550 board can support 4×16GB, but four DIMMs put more stress on the memory controller. DDR4-3600 may work with XMP enabled, though you might need to lower it to 3200 or adjust settings if the system is unstable. For ordinary gaming, 32GB is generally enough, but hosting several worlds and running lots of mods or background applications can make 64GB worthwhile if the price difference is small.

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