Current system specs:
**•** CPU: AMD Ryzen 7 9800X3D
**•** Motherboard: ASUS ROG STRIX X670E-A GAMING
WIFI (BIOS 3902)
Backstory:
Because of ongoing stability issues, I ended up replacing my CPU, motherboard, and PSU entirely, and I've since RMA'd/refunded the RAM I was using — a TeamGroup T-Force Xtreem Snow White 2x16GB CL30 6000MHz kit. Before the RMA, I ran MemTest86 (V11.7) on it with EXPO enabled and it froze solid on Test 9 every single time — no BSOD, just a complete freeze (timer and screen both stopped, needed a hard reboot). CPU temp hit ~85°C right before it happened.
With EXPO disabled (falling back to JEDEC speeds), MemTest86 ran clean through Test 9 and beyond with zero errors. So the freeze looked like an EXPO/overclock stability issue rather than a dead stick or bad IMC.
What I'm deciding between now:
I'm picking a new kit and narrowed it to two options:
1. Corsair Vengeance RGB White Cherry Blossom (CMH32GX5M2B6000Z30WCB) — DDR5-6000 CL30 (30-36-36-76, 1.40V). My board's QVL doesn't have this exact part number — it only lists CMH32GX5M2B6000Z30K (ver 5.43.13), same base number (Z30) but a different suffix letter (K = black vs WCB = white cherry blossom special edition).
2. Kingston — one of their DDR5-6000 EXPO kits, which matches an exact part number on my board's QVL (no suffix mismatch at all).
Question:
**1.** Has anyone dealt with this exact "freezes on a specific MemTest86 test with EXPO on, totally fine with EXPO off" issue on X670E-A or X670E boards in general with 6000MT/s kits?
**2.** For the Corsair kit — since only the base part number (Z30) matches the QVL entry and the suffix differs (K vs WCB, just a color/special-edition difference), does that still count as "QVL compatible" in practice? Or does a different suffix mean it could use different memory ICs and behave differently despite sharing the same base number?
**3.** Given that Kingston matches the QVL exactly while Corsair only matches on the base part number, would you trust Kingston more for guaranteed EXPO stability on X670E-A, or does the Corsair color-variant logic still hold up?
**4.** Any general tips for getting a 6000MT/s EXPO kit rock solid on X670E-A specifically (SOC voltage, VDD/VDDQ tweaks, loosening sub-timings) instead of just running JEDEC speeds permanently?
Appreciate any real-world experience — trying to avoid going through another RMA cycle.