15 specifications

Intel Core i9-10900K vs Intel Core Ultra 5 225F

On paper, the Intel Core i9-10900K boosts higher. Specifications describe what each chip is designed to do; how much of that either one holds under continuous load is a separate question.

10 specifications · 3 with a higher side

Full specifications

Intel Core i9-10900K

Intel · Comet Lake (10th gen) · Desktop

Full specifications

Intel Core Ultra 5 225F

Intel · Arrow Lake-S (Core Ultra 200S) · Desktop

Cores and clocks

Cores

Threads

Base clock

3.7 GHz

3.3 GHz

Boost clock

5.3 GHz

4.9 GHz

Cache and power

L3 cache

20 MB

TDP

125 W

65 W

Platform

Socket

FCLGA1200

FCLGA1851

Process

14 nm

3 nm

Integrated graphics

Intel UHD Graphics 630

None

Launched

2020-04

Not verified

A check marks the higher figure only on rows where higher is unambiguously better. Rows without one are not ties; they are specifications where “better” has no meaning.

Reading the table

What the difference means.

Cores and threads

The Core i9-10900K has 10 cores and 20 threads against 10 and 10. More threads help with work that can be split into many pieces at once: rendering, compiling, video export, running several heavy programs together. They do little for work that runs on a few threads, which includes most games and most everyday software, where the speed of one core decides the result.

Boost clock

The Core i9-10900K boosts to 5.3 GHz against 4.9 GHz, 8 percent higher. Across generations it is not a guide to speed on its own, for the reason above. Boost is also a peak: it is held for seconds to minutes, on one or two cores, while the cooling and the power limit allow. What either chip settles at under a long load is lower, and it depends on the cooler and the motherboard as much as the chip.

Power and cooling

The Core i9-10900K is rated at 125 W against 65 W. The rating is the heat the cooler has to move for the chip to hold its speed, and modern chips draw well above it in short bursts. A tower cooler or a liquid loop suits the Core i9-10900K; the Core Ultra 5 225F is easier to keep quiet and fits smaller cases. A chip whose cooling falls short does not fail. It slows down, and it does so after the first minute, which is why short benchmarks miss it.

Platform

They use different sockets, FCLGA1200 and FCLGA1851, so moving from one to the other means a new motherboard, and new memory as well: FCLGA1200 takes DDR4, FCLGA1851 takes DDR5. For an upgrade, that cost belongs in the comparison; for a new build, the newer platform is the one with later chips still to come.

Graphics on the chip

The Core i9-10900K includes Intel UHD Graphics 630; the Core Ultra 5 225F has no graphics of its own and will not show a picture without a graphics card. For a build with a card that changes nothing. For an office machine, a home server, or while waiting for a card, it decides the question.

Manufacturing process

The Core Ultra 5 225F is built on a 3 nm process against 14 nm. A finer process generally does the same work for less power. The names are marketing labels rather than measurements, though, and they are not comparable between manufacturers, so treat the row as a sign of how recent the design is and no more.

Which to pick, on paper

Rendering, compiling, video export: Core i9-10900K; 20 threads against 10. Work that uses every thread scales with how many there are.
A quiet or compact build: Core Ultra 5 225F; 65 W against 125 W: less heat to move, so a smaller cooler and slower fans.
No graphics card: Core i9-10900K; It has Intel UHD Graphics 630 on the chip. The other needs a card to display anything.

What no table says

How much of its speed a processor keeps after the first minute depends on the cooling and the power limit of the machine it is in. If you own one of these, measure it: the test is free and runs in this browser.

Free CPU stress test

Questions

Is the Core i9-10900K better than the Core Ultra 5 225F?: By need, on the specifications: rendering, compiling, video export: the Core i9-10900K; a quiet or compact build: the Core Ultra 5 225F; no graphics card: the Core i9-10900K. No specification says how much speed either one keeps under a long load; that depends on the cooling and the power limit of the machine it is in, and it is what a sustained test measures.
Do the Core i9-10900K and the Core Ultra 5 225F use the same socket?: No. The Core i9-10900K uses FCLGA1200 and the Core Ultra 5 225F uses FCLGA1851, so switching means a new motherboard and new memory.
Does the Core i9-10900K or the Core Ultra 5 225F have integrated graphics?: Only the Core i9-10900K, which has Intel UHD Graphics 630. The Core Ultra 5 225F needs a graphics card to show a picture.
Which runs hotter, the Core i9-10900K or the Core Ultra 5 225F?: The Core i9-10900K is rated at 125 W against 65 W, so it produces more heat under load and needs the larger cooler. How hot either one actually runs depends on the cooler and the case more than on the chip.

More comparisons

Every figure on this table is a design target. None of it is a measurement.

Nothing above describes how a processor behaves twenty minutes into a sustained workload, which is where two chips with nearly identical specifications routinely diverge. A boost clock is a ceiling the vendor permits, not a rate the chip sustains, and whether it holds depends on the cooling, the case, the power profile and the room. None of those appear on a specification sheet.

We deliberately do not reduce these figures to a single score. A composite invented from specifications would look authoritative and measure nothing, and choosing the weights would be choosing the winner.

Run the test on your machine How we measure →