Core i7-8665U vs Ryzen 7 5800X

Core i7-8665U vs Ryzen 7 5800X Performance Spectrum

Core i7-8665U

4 / 8

6,202

0.0%

27,712

+346.8%

Ryzen Threadripper 3990X

Ryzen Threadripper PRO 9965WX

About PassMark

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.

Core i7-8665U vs Ryzen 7 5800X FPS Benchmarks

Predicted gaming performance across popular games. Tested paired with GeForce RTX 5090 to isolate CPU performance.

Search any supported game below to compare 1080p FPS for both components.

Core i7-8665U vs Ryzen 7 5800X: Pros, Cons & Final Verdict

See where each CPU makes more sense in practice: gaming, heavier work, platform cost, power draw, and upgrade path.

Core i7-8665U

2019

Why buy it

✅Draws 15W instead of 105W, a 90W reduction.

Trade-offs

❌Worse for gaming: lower average FPS than Ryzen 7 5800X across 50 shared CPU benchmark tests.
❌Lower PassMark (6,202 vs 27,712).
❌Smaller total L3 cache (8 MB vs 32 MB).

Ryzen 7 5800X

2020

Why buy it

✅Better for gaming: +98.4% higher average FPS across 50 shared CPU benchmark tests.
✅+300% larger total L3 cache (32 MB vs 8 MB).
✅100+% more PCIe lanes (24 vs 0) for storage and expansion-heavy builds.

Trade-offs

❌Launch MSRP is still $449 MSRP, while Core i7-8665U mostly shows up through inconsistent older-market listings.
❌600% higher power demand at 105W vs 15W.

Quick Answers

So, is Ryzen 7 5800X better than Core i7-8665U?

Yes. Ryzen 7 5800X is the better all-around CPU here. It gives you a 98.4% average FPS lead across 50 shared CPU game tests in our data, 346.8% better PassMark, and the stronger long-term platform, which is enough to make it the stronger overall pick.

Which one is better for gaming?

If gaming is the priority, Ryzen 7 5800X is the better pick. According to our tests, it delivers 98.4% more average FPS across 50 shared CPU game tests.

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

For streaming, content creation, and heavier multitasking, Ryzen 7 5800X is the stronger fit. You are getting 346.8% better PassMark, backed by 8 cores and 16 threads. It also has the larger cache pool with 300% larger total L3 cache (32 MB vs 8 MB).

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

Ryzen 7 5800X is the better buy right now. Ryzen 7 5800X comes in at an unclear MSRP at $449 MSRP versus unclear MSRP, and it still gives you a 98.4% average FPS lead across 50 shared CPU game tests in our data. It is also 100.0% better value on MSRP (61.7 vs 0.0 PassMark/$), so you are getting the faster CPU without taking a value hit on paper.

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

Ryzen 7 5800X makes more sense long term for 2026 and beyond. You are getting a newer CPU generation (2020 vs 2019), 300% larger total L3 cache (32 MB vs 8 MB), and more multi-core headroom with 8 cores / 16 threads instead of 4/8. That extra compute headroom is more likely to matter as games, background tasks, and creator workloads get heavier.

Core i7-8665U vs Ryzen 7 5800X Technical Specifications

Side-by-side specs, architecture details, clocks, memory, power, and platform differences.

Core i7-8665U

The Core i7-8665U is manufactured by Intel. It was released in 1 October 2018 (7 years ago). It is based on the Whiskey Lake-U (2018−2019) architecture. It features 4 cores and 8 threads. Base frequency is 1.9 GHz, with boost up to 4.8 GHz. L3 cache: 8 MB (total). L2 cache: 256 kB (per core). Built on 14 nm process technology. Socket: FCBGA1528. Thermal design power (TDP): 15 Watt. Memory support: DDR4. Passmark benchmark score: 6,202 points. Launch price was $409.

Ryzen 7 5800X

The Ryzen 7 5800X is manufactured by AMD. It was released in 5 November 2020 (5 years ago). It is based on the Vermeer (Zen 3) (2020−2022) architecture. It features 8 cores and 16 threads. Base frequency is 3.8 GHz, with boost up to 4.7 GHz. L3 cache: 32 MB. L2 cache: 512K (per core). Built on 7 nm, 12 nm process technology. Socket: AM4. Thermal design power (TDP): 105 Watt. Memory support: DDR4. Passmark benchmark score: 27,712 points. Launch price was $449.

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Processing Power

The Core i7-8665U packs 4 cores / 8 threads, while the Ryzen 7 5800X offers 8 cores / 16 threads — the Ryzen 7 5800X has 4 more cores. Boost clocks reach 4.8 GHz on the Core i7-8665U versus 4.7 GHz on the Ryzen 7 5800X — a 2.1% clock advantage for the Core i7-8665U (base: 1.9 GHz vs 3.8 GHz). The Core i7-8665U uses the Whiskey Lake-U (2018−2019) architecture (14 nm), while the Ryzen 7 5800X uses Vermeer (Zen 3) (2020−2022) (7 nm, 12 nm). In PassMark, the Core i7-8665U scores 6,202 against the Ryzen 7 5800X's 27,712 — a 126.9% lead for the Ryzen 7 5800X. L3 cache: 8 MB (total) on the Core i7-8665U vs 32 MB on the Ryzen 7 5800X.

Feature	Core i7-8665U	Ryzen 7 5800X
Cores / Threads	4 / 8	8 / 16+100%
Boost Clock	4.8 GHz+2%	4.7 GHz
Base Clock	1.9 GHz	3.8 GHz+100%
L3 Cache	8 MB (total)	32 MB+300%
L2 Cache	256 kB (per core)	512K (per core)+100%
Process	14 nm	7 nm, 12 nm-50%
Architecture	Whiskey Lake-U (2018−2019)	Vermeer (Zen 3) (2020−2022)
PassMark	6,202	27,712+347%

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Memory & Platform

The Core i7-8665U uses the FCBGA1528 socket (PCIe 3.0), while the Ryzen 7 5800X uses AM4 (PCIe 4.0) — making them incompatible on the same motherboard.

Feature	Core i7-8665U	Ryzen 7 5800X
Socket	FCBGA1528	AM4
PCIe Generation	PCIe 3.0	PCIe 4.0+33%
Max RAM Speed	—	DDR4-3200
Max RAM Capacity	—	128 GB
RAM Channels	—	2
ECC Support	—	Yes
PCIe Lanes	—	24