CPU-Z is all you need for RAM compatibility.

Yes, CPU-Z shows the exact specs you need to match.

Open CPU-Z, click the SPD tab, and pick a slot. It will tell you the module’s type (DDR4, DDR5), speed (e.g., 3200 MHz), timings (e.g., CL16-18-18-38), voltage, and whether it’s single or dual rank. That’s your target.

For a new stick, check two things: First, the type and speed must match your existing stick exactly—mixing DDR4 and DDR5 won’t work, and mismatched speeds will downclock both. Second, timings should be the same or looser. Tighter timings might cause instability. Voltage too—1.2V vs 1.35V can be a problem unless your motherboard handles it.

If you’re adding a second stick, also check if your motherboard supports dual-channel with that configuration. CPU-Z’s Memory tab shows you current channel mode (single vs dual). If it’s already dual, adding a mismatched stick will likely drop it back to single—worse performance. The stick you’re adding should match the existing one’s rank (single or dual) for best results.

Bottom line: grab the SPD data from CPU-Z, match type, speed, timings, and voltage, and you’re good. If you’re unsure, just buy an identical kit to what you already have.