A Reddit user posting as SpecialistConcept423 in r/GamersNexus reported that his AMD Ryzen 9 9950X3D died about an hour after he moved it from an ASRock X670E Taichi Carrara, where it had run without issue for roughly a year and a half, into an ASUS ROG Crosshair X670E Hero motherboard. According to both TechPowerUp and Wccftech, no manual overclocking or voltage adjustments were made to the CPU or RAM during the swap. The user did enable one of the motherboard's built-in memory presets for a pair of SK Hynix 6200MHz modules.
After saving that memory preset and rebooting, the system failed to post and displayed a "00" Q-Code, according to both outlets. When the CPU was removed for inspection, two brown marks were visible on its contacts, which both sources describe as pointing to catastrophic chip failure. Wccftech notes the motherboard was reportedly running the latest available BIOS version at the time.
The situation grew more unusual when the user tried an older Ryzen 5 8500G, which had previously worked fine on the same board, as a backup. Both sources report that this second CPU also failed, with the board this time showing a "4D" error code. TechPowerUp states the user confirmed there were no bent pins on the motherboard, suggesting the board itself, rather than just the CPU, may be responsible. Neither source has confirmed whether a faulty BIOS, a bad batch of boards, or another cause is to blame, and ASUS has not commented on this specific case.
TechPowerUp adds relevant context: the ASUS board in question was not new and had previously undergone USB-related repairs along with a BIOS rewrite. The user has since contacted AMD in Brazil to request an RMA, but no updates on that process have been shared yet.
Both outlets note this isn't the first CPU failure associated with the same ASUS ROG Crosshair X670E Hero model or with high-performance Ryzen chips more broadly. TechPowerUp points to a Ryzen 7 7800X3D that reportedly swelled and burned on the same board model just days earlier, as well as ASRock's past admission that overly aggressive PBO current limits damaged a number of Ryzen 9000 chips on its motherboards. Wccftech separately references an earlier case of a Ryzen 9 9950X3D dying within nine days of use on an ASRock motherboard. Neither source confirms whether these incidents share a common root cause, but both frame the repeated failures on this particular board as noteworthy.
Wccftech's report concludes that, based on the user's account of not applying manual voltage changes and only selecting a preset already included in the BIOS, the user appears to deserve a refund, though this reflects the outlet's own assessment rather than a confirmed finding from AMD or ASUS.