Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | Intel - Core Ultra 9 285K | AMD - Ryzen 9 9900X3D |
|---|---|---|
| L3 cache | 36 MB | 128 MB |
| Cores | 24 | 12 |
| Cinebench R23 (multi) | 42800 | 33500 |
| TDP | 125 W | 120 W |
| Boost clock | 5.7 GHz | 5.5 GHz |
Between the Core Ultra 9 285K and Ryzen 9 9900X3D, the Core Ultra 9 285K comes out ahead in cores / cinebench r23 (multi), while the Ryzen 9 9900X3D wins on l3 cache / tdp. Overall, the Core Ultra 9 285K scores 60.9 and the Ryzen 9 9900X3D scores 58.1 on our Mars Score.
Which should you buy?
These two are nearly even on the Mars Score (60.9 vs 58.1). The decision is not about overall quality — both clear the bar — it is about which specific trade-offs fit your use.
Pick the Core Ultra 9 285K 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), boost clock. The single most decisive one: Cores — 100.00% more. 24 vs 12.
Pick the Ryzen 9 9900X3D if you care most about l3 cache / tdp. Its strongest claims are l3 cache, tdp. The single most decisive one: L3 cache — 255.56% more. 128 MB vs 36 MB.
There are no meaningful ties on the headline specs — every popular-comparison metric has a winner.
Bottom line: there is no wrong answer here — match the spec advantages to how you actually use the product. The Mars Score parity says both are well-rounded; the differences are about trade-offs, not quality.
Which should you buy: Intel - Core Ultra 9 285K or AMD - Ryzen 9 9900X3D?
Intel - Core Ultra 9 285K leads the current Mars Score by 2.8 points.The more useful decision is the trade-off behind that result: compare cores, boost clock, tdp against the way you will actually use the product.
Choose Intel - Core Ultra 9 285K if…
Intel - Core Ultra 9 285K has the measurable edge on core count, cinebench r23 multi, boost clock ghz.
Choose AMD - Ryzen 9 9900X3D if…
AMD - Ryzen 9 9900X3D has the measurable edge on cache l3 mb, tdp w.
This is a structured comparison of the published catalog values. It is not a claim of identical real-world performance across every workload; use the linked spec drill-downs and methodology page to inspect the inputs.
Why Intel - Core Ultra 9 285K wins
- ▲Cores — 100.00% more. 24 vs 12.
- ▲Cinebench R23 (multi) — 27.76% more. 42800 vs 33500.
- ▲Boost clock — 3.64% more. 5.7 GHz vs 5.5 GHz.
Why AMD - Ryzen 9 9900X3D wins
- ▲L3 cache — 255.56% more. 128 MB vs 36 MB.
- ▲TDP — 5.00 W less. 120 vs 125.
Spec comparison
Cores
| Spec | Intel - Core Ultra 9 285K | AMD - Ryzen 9 9900X3D |
|---|---|---|
| Coresⓘ | 24lead | 12 |
| Threadsⓘ | 24 | 24 |
| Base clockⓘ | 3.7 GHz | 4.4 GHzlead |
| Boost clockⓘ | 5.7 GHzlead | 5.5 GHz |
| L3 cacheⓘ | 36 MB | 128 MBlead |
Platform
| Spec | Intel - Core Ultra 9 285K | AMD - Ryzen 9 9900X3D |
|---|---|---|
| Socketⓘ | LGA1851 | AM5 |
| TDPⓘ | 125 W | 120 Wlead |
| Integrated graphicsⓘ | true | true |
| DDR5ⓘ | true | true |
Benchmarks
| Spec | Intel - Core Ultra 9 285K | AMD - Ryzen 9 9900X3D |
|---|---|---|
| Cinebench R23 (multi)ⓘ | 42800lead | 33500 |
| Cinebench R23 (single)ⓘ | 2230 | 2240lead |