Processors/Comparison
15 specifications
Intel Core i3-9100 vs Intel Core i7-6700K
On paper, the Intel Core i7-6700K carries more L3 cache. Specifications describe what each chip is designed to do; how much of that either one holds under continuous load is a separate question.
Intel Core i3-9100
Intel · Core 9th generation · Desktop
Intel Core i7-6700K
Intel · Core 6th generation · Desktop
Cores and clocks
Cache and power
Platform
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 i7-6700K has 4 cores and 8 threads against 4 and 4. 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.
Cache
The Core i7-6700K carries 8 MB of L3 cache against 6 MB. Cache is fast memory on the chip, and a larger one means the cores wait on main memory less often. Games, large spreadsheets and compiling respond to it; rendering and video export, which stream through data in order, respond much less.
Power and cooling
The Core i7-6700K is rated at 91 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 competent tower cooler suits the Core i7-6700K; the Core i3-9100 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
Both use the FCLGA1151 socket, so one can replace the other on the same motherboard. Check the board maker's support list first: an older board often needs a firmware update before it recognises a newer chip.
Which to pick, on paper
- Rendering, compiling, video export
- Core i7-6700K
- 8 threads against 4. Work that uses every thread scales with how many there are.
- A quiet or compact build
- Core i3-9100
- 65 W against 91 W: less heat to move, so a smaller cooler and slower fans.
- Upgrading without a new motherboard
- Either
- Same FCLGA1151 socket. Update the board's firmware before swapping.
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.
Questions
- Is the Core i3-9100 better than the Core i7-6700K?
- By need, on the specifications: rendering, compiling, video export: the Core i7-6700K; a quiet or compact build: the Core i3-9100; upgrading without a new motherboard: either. 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 i3-9100 and the Core i7-6700K use the same socket?
- Yes, both use FCLGA1151, so either fits the other's motherboard. Check the board's support list and update its firmware first.
- Does the Core i3-9100 or the Core i7-6700K have integrated graphics?
- Both do: Intel UHD Graphics 630 on the Core i3-9100 and Intel HD Graphics 530 on the Core i7-6700K.
- Which runs hotter, the Core i3-9100 or the Core i7-6700K?
- The Core i7-6700K is rated at 91 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
- Intel Core i3-9100 vs AMD Ryzen 3 3100
- Intel Core i3-9100 vs Intel Core i3-10100
- Intel Core i3-9100 vs Intel Core i7-6700
- Intel Core i3-9100 vs AMD FX-4350
- Intel Core i3-9100 vs AMD A8-6600K with Radeon HD 8570D
- Intel Core i7-6700K vs Intel Core i3-10100
- Intel Core i7-6700K vs AMD Ryzen 3 3100
- Intel Core i7-6700K vs AMD FX-4350
- Intel Core i7-6700K vs Intel Core i7-4790K
- Intel Core i7-6700K vs Intel Core i7-6700
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.