I upgraded my PC from a single 16GB DDR5 stick in slot A2 to two 16GB sticks. The system runs with one stick in A2, and it also boots when both sticks are installed in A1 and B1, but it will not start when they are placed in the recommended A2 and B2 slots. The new modules are Corsair DDR5, while the previous stick was a T-Force DDR5 module. I have not enabled XMP, EXPO, or any manual overclocking. My motherboard is a Z690-C/D5. Is it safe to keep using A1 and B1, or could that damage the computer?
2 Answers
Using A1 and B1 should not damage the motherboard or memory. However, A2 and B2 are usually the preferred slots for two modules because they tend to provide the best signal quality and compatibility. Running in A1 and B1 may work, but it could limit maximum memory speed or stability. Since the sticks are different brands, make sure their capacity, speed, timings, and voltage match, and test them at the motherboard's default settings first.
Try clearing the CMOS, then boot with only one stick in A2 and update the BIOS if necessary. After that, install both matching modules in A2 and B2 with memory overclocking disabled. DDR5 can require memory training after changing the configuration, so give the first boot a few minutes. Also confirm that the modules are fully seated; both latches should lock into place.
If A2 works but B2 never works even with a known-good stick, inspect the slot for debris and check for bent CPU-socket pins. On many boards, a memory-channel problem can come from the CPU socket or cooler pressure, not just the RAM itself.
It is also worth checking the motherboard manual and testing each stick individually in A2. If one module or the B2 slot fails by itself, the issue may be a bad DIMM, a socket problem, or CPU socket contact rather than the slot arrangement.