I built this PC in early 2020 and recently noticed that my DDR4-3600 memory is running below its rated speed. I originally had one 2x16GB kit, then added a second identical kit for 64GB total. I suspect the extra DIMMs caused the system to fall back to a lower memory speed, possibly because of memory-controller limitations or BIOS settings.
The system uses a Ryzen 7 3700X, Asus ROG STRIX B550-F GAMING motherboard, 64GB of DDR4-3600 CL16, and an RTX 2080 Ti driving a 3440x1440 144Hz monitor. It is primarily used for gaming. I'm considering a Ryzen 7 5800X or 5800X3D and would like to keep the upgrade around $350–$400, including any cooler upgrade if necessary. Is replacing the CPU the best way to address the memory-speed issue, or should I simply re-enable DOCP/XMP and adjust the RAM configuration?
2 Answers
First check the BIOS before buying anything. Enable DOCP, which is ASUS’s name for the memory profile that sets the kit to its rated speed. Adding a second 2x16GB kit can make the memory controller less stable, so the motherboard may automatically lower the speed when all four slots are populated. If you don’t actually need 64GB, using only one matched 32GB kit may let you run DDR4-3600 more easily.
For gaming, a Ryzen 5 5600X would already be a sensible and relatively inexpensive upgrade from the 3700X, especially at 3440x1440 where the graphics card is often the limiting factor. A 5800X3D is the strongest gaming upgrade for this AM4 motherboard, but it only makes sense if you want higher minimum frame rates or plan to upgrade the graphics card later. It won’t directly solve a RAM configuration problem, so fix the DOCP and four-DIMM settings first.
That makes sense. I was assuming the CPU was responsible for the slow memory, but it sounds like the BIOS profile and running four modules may be the more immediate issue.
I had DOCP enabled with the original two sticks, but it seems to have been disabled after I installed the second kit. I’ll check the BIOS again and test the memory configuration.