PassMark CPU Mark evaluates processor speed through complex mathematical computations. It provides a reliable metric to compare multi-core performance, where higher scores indicate faster processing for multitasking, gaming, and heavy workloads.

Head-to-Head Verdict, Benchmarks, Value & Long-Term Outlook

This comparison brings together gaming FPS, productivity performance, platform differences, power efficiency, pricing context, and upgrade path so you can see which CPU actually makes more sense.

Core i5-10400F

2020

Why buy it

✅Costs $929 less on MSRP ($160 MSRP vs $1,089 MSRP).
✅Delivers 504.0% more PassMark for each dollar spent, at 81.4 vs 13.5 PassMark/$ ($160 MSRP vs $1,089 MSRP).
✅Draws 65W instead of 140W, a 75W reduction.
✅Includes a boxed cooler (Yes), unlike Core i7-6900K.

Trade-offs

❌Worse for gaming: lower average FPS than Core i7-6900K across 4 shared CPU benchmark tests.
❌Lower Geekbench multi-core (5,783 vs 7,591).
❌Smaller total L3 cache (12 MB vs 20 MB).

Core i7-6900K

2016

Why buy it

✅Better for gaming: +4.9% higher average FPS across 4 shared CPU benchmark tests.
✅+66.7% larger total L3 cache (20 MB vs 12 MB).
✅150% more PCIe lanes (40 vs 16) for storage and expansion-heavy builds.

Trade-offs

❌Lower PassMark per dollar, at 13.5 vs 81.4 PassMark/$ ($1,089 MSRP vs $160 MSRP).
❌115.4% higher power demand at 140W vs 65W.
❌No boxed cooler included, unlike Core i5-10400F.

Core i5-10400F

2020

Core i7-6900K

2016

Why buy it

✅Costs $929 less on MSRP ($160 MSRP vs $1,089 MSRP).
✅Delivers 504.0% more PassMark for each dollar spent, at 81.4 vs 13.5 PassMark/$ ($160 MSRP vs $1,089 MSRP).
✅Draws 65W instead of 140W, a 75W reduction.
✅Includes a boxed cooler (Yes), unlike Core i7-6900K.

Why buy it

✅Better for gaming: +4.9% higher average FPS across 4 shared CPU benchmark tests.
✅+66.7% larger total L3 cache (20 MB vs 12 MB).
✅150% more PCIe lanes (40 vs 16) for storage and expansion-heavy builds.

Trade-offs

❌Worse for gaming: lower average FPS than Core i7-6900K across 4 shared CPU benchmark tests.
❌Lower Geekbench multi-core (5,783 vs 7,591).
❌Smaller total L3 cache (12 MB vs 20 MB).

Trade-offs

❌Lower PassMark per dollar, at 13.5 vs 81.4 PassMark/$ ($1,089 MSRP vs $160 MSRP).
❌115.4% higher power demand at 140W vs 65W.
❌No boxed cooler included, unlike Core i5-10400F.

Quick Answers

So, is Core i7-6900K better than Core i5-10400F?

Yes. Core i7-6900K is the better overall CPU here. You are getting a 4.9% average FPS lead across 4 shared CPU game tests in our data, 31.3% better Geekbench multi-core, and 12.7% higher PassMark, which makes it the stronger all-around choice.

Which one is better for gaming?

If gaming is the priority, Core i7-6900K is the better pick here. According to our tests, it delivers 4.9% more average FPS across 4 shared CPU game tests.

Which one is better for streaming, content creation, and heavy multitasking?

For streaming, content creation, and heavier multitasking, Core i7-6900K is the better fit. You are getting 31.3% better Geekbench multi-core, backed by 8 cores and 16 threads. It also carries the larger cache pool with 66.7% larger total L3 cache (20 MB vs 12 MB).

Which one is the smarter buy today, not just the cheaper CPU?

Core i7-6900K is still the faster CPU overall, but Core i5-10400F makes more sense if price matters more than absolute performance. Core i7-6900K is 580.6% more expensive on MSRP at $1,089 MSRP versus $160 MSRP, and it gives you a 4.9% average FPS lead across 4 shared CPU game tests in our data. Core i5-10400F is also 504.0% better value on MSRP (81.4 vs 13.5 PassMark/$), which is why it is easier to justify for price-conscious builds on paper. That said, if you already own a compatible LGA1200 + DDR4 setup, Core i5-10400F can still make sense as a platform-matched option because it avoids a motherboard and RAM swap.

Which one is more future-proof for 2026 and beyond?

Core i5-10400F is the more future-proof choice for 2026 and beyond. You are getting a newer CPU generation (2020 vs 2016). That makes it the safer long-term pick.

Games Benchmarks

Paired with RTX 4090

To accurately isolate CPU performance, all benchmarks below use an NVIDIA RTX 4090 as the reference GPU. This eliminates GPU-side bottlenecks and highlights pure processing throughput differences between the CPUs.

Note: Real-world results may vary based on your actual GPU. CPU performance impact is more visible in processing-intensive titles and high-refresh-rate gaming scenarios.

Core i5-10400F Benchmark Check

Core i7-6900K Benchmark Check

Path of Exile 2

Preset	Core i5-10400F	Core i7-6900K
1080p
low	192 FPS	173 FPS
medium	152 FPS	139 FPS
high	123 FPS	113 FPS
ultra	100 FPS	90 FPS
1440p
low	153 FPS	144 FPS
medium	119 FPS	113 FPS
high	97 FPS	90 FPS
ultra	79 FPS	71 FPS
4K
low	82 FPS	66 FPS
medium	70 FPS	55 FPS
high	55 FPS	44 FPS
ultra	43 FPS	35 FPS

Open Core i5-10400F Open Core i7-6900K

Path of Exile 2

Path of Exile 2

Counter-Strike 2

Preset	Core i5-10400F	Core i7-6900K
1080p
low	326 FPS	367 FPS
medium	318 FPS	329 FPS
high	290 FPS	274 FPS
ultra	253 FPS	230 FPS
1440p
low	326 FPS	329 FPS
medium	292 FPS	291 FPS
high	267 FPS	243 FPS
ultra	234 FPS	202 FPS
4K
low	309 FPS	212 FPS
medium	258 FPS	189 FPS
high	235 FPS	168 FPS
ultra	199 FPS	138 FPS

Open Core i5-10400F Open Core i7-6900K

Counter-Strike 2

Counter-Strike 2

League of Legends

Preset	Core i5-10400F	Core i7-6900K
1080p
low	326 FPS	367 FPS
medium	326 FPS	367 FPS
high	326 FPS	367 FPS
ultra	326 FPS	367 FPS
1440p
low	326 FPS	367 FPS
medium	326 FPS	367 FPS
high	326 FPS	367 FPS
ultra	326 FPS	367 FPS
4K
low	326 FPS	367 FPS
medium	326 FPS	367 FPS
high	289 FPS	361 FPS
ultra	229 FPS	295 FPS

Open Core i5-10400F Open Core i7-6900K

League of Legends

League of Legends

Valorant

Preset	Core i5-10400F	Core i7-6900K
1080p
low	326 FPS	367 FPS
medium	326 FPS	367 FPS
high	326 FPS	367 FPS
ultra	326 FPS	367 FPS
1440p
low	326 FPS	367 FPS
medium	326 FPS	367 FPS
high	326 FPS	367 FPS
ultra	326 FPS	367 FPS
4K
low	326 FPS	367 FPS
medium	326 FPS	367 FPS
high	326 FPS	367 FPS
ultra	326 FPS	367 FPS

Open Core i5-10400F Open Core i7-6900K

Valorant

Valorant

Check FPS for your specific build

Technical Specifications

Side-by-side comparison of Core i5-10400F and Core i7-6900K

Core i5-10400F

The Core i5-10400F is manufactured by Intel. It was released in 30 April 2020 (5 years ago). It is based on the Comet Lake (2020−2025) architecture. It features 6 cores and 12 threads. Base frequency is 2.9 GHz, with boost up to 4.3 GHz. L3 cache: 12 MB (total). L2 cache: 256K (per core). Built on 14 nm process technology. Socket: LGA1200. Thermal design power (TDP): 65 Watt. Memory support: DDR4. Passmark benchmark score: 13,029 points. Launch price was $155.

Core i7-6900K

The Core i7-6900K is manufactured by Intel. It was released in 31 May 2016 (9 years ago). It is based on the Broadwell-E (2016) architecture. It features 8 cores and 16 threads. Base frequency is 3.2 GHz, with boost up to 4 GHz. L3 cache: 20 MB (total). L2 cache: 256 kB (per core). Built on 14 nm process technology. Socket: LGA2011. Thermal design power (TDP): 140 Watt. Memory support: DDR4. Passmark benchmark score: 14,682 points. Launch price was $1,020.

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Processing Power

The Core i5-10400F packs 6 cores / 12 threads, while the Core i7-6900K offers 8 cores / 16 threads — the Core i7-6900K has 2 more cores. Boost clocks reach 4.3 GHz on the Core i5-10400F versus 4 GHz on the Core i7-6900K — a 7.2% clock advantage for the Core i5-10400F (base: 2.9 GHz vs 3.2 GHz). The Core i5-10400F uses the Comet Lake (2020−2025) architecture (14 nm), while the Core i7-6900K uses Broadwell-E (2016) (14 nm). In PassMark, the Core i5-10400F scores 13,029 against the Core i7-6900K's 14,682 — a 11.9% lead for the Core i7-6900K. Geekbench 6 single-core — the metric most relevant to gaming — records 1,454 vs 1,273, a 13.3% lead for the Core i5-10400F that directly translates to higher frame rates. Multi-core Geekbench: 5,783 vs 7,591 (27% advantage for the Core i7-6900K). L3 cache: 12 MB (total) on the Core i5-10400F vs 20 MB (total) on the Core i7-6900K.

Feature	Core i5-10400F	Core i7-6900K
Cores / Threads	6 / 12	8 / 16+33%
Boost Clock	4.3 GHz+7%	4 GHz
Base Clock	2.9 GHz	3.2 GHz+10%
L3 Cache	12 MB (total)	20 MB (total)+67%
L2 Cache	256K (per core)	256 kB (per core)
Process	14 nm	14 nm
Architecture	Comet Lake (2020−2025)	Broadwell-E (2016)
PassMark	13,029	14,682+13%
Cinebench R23 Multi	8,191	—
Geekbench 6 Single	1,454+14%	1,273
Geekbench 6 Multi	5,783	7,591+31%

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Memory & Platform

The Core i5-10400F uses the LGA1200 socket (PCIe 3.0), while the Core i7-6900K uses LGA2011 (PCIe 3.0) — making them incompatible on the same motherboard. Both support up to DDR4-2666 memory speed. Both support up to 128 GB of RAM. Memory channels: 2 (Core i5-10400F) vs 4 (Core i7-6900K). PCIe lanes: 16 (Core i5-10400F) vs 40 (Core i7-6900K) — the Core i7-6900K offers 24 more lanes for additional GPUs or NVMe drives. Chipset compatibility: H410,B460,H470,Z490,H510,B560,H570,Z590 (Core i5-10400F) and X99 (Core i7-6900K).

Feature	Core i5-10400F	Core i7-6900K
Socket	LGA1200	LGA2011
PCIe Generation	PCIe 3.0	PCIe 3.0
Max RAM Speed	DDR4-2666	DDR4-2400
Max RAM Capacity	128 GB	128 GB
RAM Channels	2	4+100%
ECC Support	No	No
PCIe Lanes	16	40+150%

🔧

Advanced Features

Only the Core i7-6900K has an unlocked multiplier for overclocking — a significant advantage for enthusiasts seeking extra performance. Both support VT-x, VT-d virtualization. Primary use case: Core i5-10400F targets Gaming, Core i7-6900K targets High-End Desktop. Direct competitor: Core i5-10400F rivals Ryzen 5 3600.

Feature	Core i5-10400F	Core i7-6900K
Integrated GPU	No	No
IGPU Model	—	None
Unlocked	No	Yes
AVX-512	No	No
Virtualization	VT-x, VT-d	VT-x, VT-d
Target Use	Gaming	High-End Desktop

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Value Analysis

The Core i5-10400F launched at $160 MSRP, while the Core i7-6900K debuted at $1089. On MSRP ($160 vs $1089), the Core i5-10400F is $929 cheaper. In terms of value on MSRP (PassMark points per dollar), the Core i5-10400F delivers 81.4 pts/$ vs 13.5 pts/$ for the Core i7-6900K — making the Core i5-10400F the 143.2% better value option.