I'm upgrading my AMD-based PC, which currently has an MSI B450 Mortar motherboard, a Ryzen 5 3600, an RX 6600 XT, and 16GB of Corsair Vengeance DDR4-3000 memory. I'm considering adding another matching 2x8GB kit to reach 32GB, but some people told me the motherboard may perform worse with four sticks installed. Is that a realistic concern, and would 2x16GB be a better choice? I'm planning to stay on this system for a while before eventually moving to AM5, so I don't want to spend unnecessarily on DDR4. I've also ordered a Ryzen 7 5700X and would like to know whether that is a worthwhile upgrade from the 3600.
4 Answers
Four sticks should work fine on the B450 Mortar, but you may need to reduce the memory speed slightly if the system becomes unstable. Try to use the exact same kit, timings, and preferably the same memory chips. Also, four sticks do not create quad-channel memory on this platform—AM4 still runs in dual channel. Check your actual RAM usage first; if games and applications aren’t using close to 16GB, the upgrade can wait.
Adding another 2x8GB kit is a reasonable and inexpensive way to reach 32GB. The motherboard is not poorly made; the B450 Mortar is generally a solid board. The main downside of four DIMMs is that the memory controller has more work to do, so DDR4-3000 may require a little manual tweaking, but it should normally be manageable.
The Ryzen 7 5700X is a good upgrade from the Ryzen 5 3600, especially in newer games and multitasking. Just remember that a B450 board and the 5700X will run PCIe 3.0, while the CPU supports PCIe 4.0. With an RX 6600 XT, that usually isn’t a major concern. Update the motherboard BIOS before installing the new CPU if necessary.
I’d install the 5700X first and monitor memory usage before buying more RAM. If you are regularly hitting around 15–16GB, upgrade to 32GB. If you do buy memory, adding a matching 2x8GB kit is fine for a budget upgrade; 2x16GB is technically the cleaner configuration, but it isn’t necessary unless you want maximum compatibility or plan to replace the existing kit.
DDR4 and DDR5 pricing alone isn’t a strong reason to switch platforms. Moving to AM5 would also require a new motherboard and CPU, so keeping the current system and upgrading only when needed makes sense.
It’s worth checking whether the existing modules are single-rank or dual-rank rather than assuming every 8GB stick is the same. Mixing kits can also cause problems even when the advertised specifications match.