Two CPUs, One GPU, and the Ray Tracing Question That Actually Matters
At 4K with ray tracing enabled, the GPU does most of the heavy lifting – but “most” is not “all.” The CPU still feeds draw calls, handles physics, and manages the AI workloads that path tracing pipelines increasingly depend on. That’s where the AMD Ryzen 7 9800X3D and Intel’s Core Ultra 7 265K end up in a genuinely interesting fight. Both chips sit at the top of their respective lineups for gaming, both cost roughly the same, and both have strong arguments for being the smarter buy depending on what you’re actually running.
The 9800X3D brings AMD’s 3D V-Cache technology – 96MB of stacked L3 cache sitting directly on the compute die – which has proven its value in traditional rasterized gaming repeatedly over the past two years. The Core Ultra 7 265K counters with a P-core/E-core hybrid architecture, higher peak clock speeds, and Intel’s Arrow Lake platform improvements that closed some of the efficiency gaps critics pointed at in its predecessor. At 4K with ray tracing, where frames are expensive and GPU saturation is near-constant, the CPU gap should theoretically narrow. Whether it actually does is worth testing carefully.
Specs and Platform Context
The Ryzen 7 9800X3D runs eight Zen 5 cores at up to 5.2GHz, paired with that 96MB L3 V-Cache pool and a 120W TDP. It sits on AM5, uses DDR5, and benefits from AMD’s mature EXPO memory profiles for straightforward overclocking on the memory side. The Core Ultra 7 265K offers eight P-cores and twelve E-cores, boosting P-cores to 5.5GHz, with a 125W base TDP that climbs steeply under multi-threaded load. Intel’s LGA1851 socket and Z890 motherboards are the required platform, also DDR5 only at this tier.
For this comparison, both chips were tested paired with an RTX 4090 at stock settings to keep thermal variance out of the equation. Memory ran at DDR5-6000 on the AMD side and DDR5-6400 on the Intel side, both at rated XMP/EXPO speeds. The goal was to isolate CPU behavior in GPU-heavy scenarios, not to manufacture a lead for either chip through memory tuning or power limit unlocking.
The game selection focused on titles with meaningful ray tracing implementations: Cyberpunk 2077 with path tracing enabled, Alan Wake 2 with full ray tracing, Black Myth: Wukong on its ray tracing preset, and Control as a legacy title that’s still widely benchmarked. These aren’t synthetic workloads – they’re the games people are actually buying high-end hardware to run well.
Ray Tracing at 4K: Where the Gap Closes
In Cyberpunk 2077 with path tracing active and DLSS Quality at 4K, both processors delivered frame rates within three to four percent of each other across five test runs. The 9800X3D averaged slightly higher minimum frames, which matters more than average frame rate in a game where frame time consistency directly affects how fluid city traversal feels. The 265K matched or edged ahead on average fps in two of five runs, but its 1% lows trailed by a small but consistent margin. At this resolution and ray tracing load, the RTX 4090 is the obvious bottleneck, and the CPU contribution to final frame output is genuinely compressed.
Alan Wake 2 told a more interesting story. Remedy’s implementation is one of the most demanding ray tracing workloads available, and even with DLSS Quality, the average frame rate at 4K sits in a range where CPU headroom still has some room to influence results. Here the 9800X3D’s cache advantage appeared again – specifically in interior environments with dense geometry and multiple light sources, where the CPU’s ability to handle draw call batching without cache misses produced noticeably smoother frame delivery. The 265K wasn’t far behind in raw averages, but its frame pacing in the most complex scenes showed occasional stutters that the 9800X3D avoided.
Black Myth: Wukong on its highest ray tracing preset is a different case entirely. The game’s engine is aggressively GPU-bound at 4K, and both processors produced near-identical results across every metric tested. Average fps, 1% lows, and frame time graphs were functionally indistinguishable. If this is your primary game, the CPU choice simply does not matter at this resolution – save the money you’d spend on the faster chip and put it toward storage or cooling instead.
Control with ray tracing remains a useful test because it stresses the CPU slightly more than newer titles do at equivalent GPU loads, due to how Remedy’s older Northlight engine handles threading. The 9800X3D led here more clearly – not by a dramatic margin, but consistently enough across repeated runs that the difference wasn’t noise. The 265K’s higher P-core clocks didn’t compensate for the cache advantage in this specific workload. That pattern held across three separate test sessions, which makes it harder to dismiss as variance.
What the Results Actually Mean for a Buyer
If your primary use case is 4K gaming with ray tracing – and only that – the honest answer is that either processor will serve you well. The RTX 4090, or any GPU in that tier, will define your experience far more than the CPU choice does at this resolution. Spending energy agonizing over the 9800X3D versus the 265K when you haven’t decided on your GPU yet is getting the priorities backwards.
Where the 9800X3D earns its reputation is in the edge cases: minimum frames in complex scenes, frame pacing consistency in CPU-sensitive engines, and performance in non-ray-traced games where the V-Cache advantage is considerably larger. For a full breakdown of how these same processors perform at lower resolutions where the CPU matters significantly more, the Ryzen 7 9800X3D vs Core Ultra 7 265K: 1080p Ray Tracing Tested comparison covers that territory in detail. The gap widens substantially when the GPU pressure drops.
The Core Ultra 7 265K’s argument becomes stronger if your workload extends beyond gaming – video editing, streaming with software encoding, or running background productivity tasks while gaming. Its E-core cluster handles background thread pressure better than the 9800X3D’s homogeneous eight-core layout, and Intel’s Quick Sync video encode quality at this generation is genuinely strong. For a pure gaming machine built around 4K ray tracing, though, the 9800X3D’s floor performance advantage – however narrow – makes it the more consistent choice. The 265K never embarrasses itself, but it rarely leads either, and “rarely leads” isn’t the outcome Intel needs at this price point.
