Apple - M4 Ultra vs AMD - Ryzen 9 9900X3D

The M4 Ultra edges ahead on the Mars Score (63.1 vs 58.1), but the 5.0-point gap is small enough that the right pick comes down to which spec advantages matter to you.

Pick the M4 Ultra if you push the hardware — gaming, on-device AI, heavy multitasking — and the extra compute headroom is worth the trade-offs. The biggest gaps in its favor are cores, cinebench r23 (multi).

Pick the Ryzen 9 9900X3D if you care most about l3 cache and boost clock. Its strongest claims are l3 cache, boost clock.

Both ship with comparable tdp, so those specs don't separate the two — focus on the differences below.

Bottom line: the M4 Ultra is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.