Athlon II X4 651 vs Core i7-6660U

Athlon II X4 651 vs Core i7-6660U Performance Spectrum

Athlon II X4 651

4 / 4

3,584

0.0%

Ryzen Threadripper 3990X

Core i7-6660U

2 / 4

3,628

+1.2%

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.

Athlon II X4 651 vs Core i7-6660U 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.

Athlon II X4 651 vs Core i7-6660U: Pros, Cons & Final Verdict

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

Athlon II X4 651

2011

Why buy it

✅Better for gaming: +4.1% higher average FPS across 50 shared CPU benchmark tests.
✅100+% more PCIe lanes (16 vs 0) for storage and expansion-heavy builds.

Trade-offs

❌Lower PassMark (3,584 vs 3,628).
❌Launch MSRP is still $92 MSRP, while Core i7-6660U mostly shows up through inconsistent older-market listings.
❌566.7% higher power demand at 100W vs 15W.

Core i7-6660U

2016

Why buy it

✅+1.2% higher PassMark.
✅Draws 15W instead of 100W, a 85W reduction.

Trade-offs

❌Worse for gaming: lower average FPS than Athlon II X4 651 across 50 shared CPU benchmark tests.

Quick Answers

So, is Core i7-6660U better than Athlon II X4 651?

It depends on what you want from the system. For gaming, Athlon II X4 651 is ahead with a 4.1% average FPS lead across 50 shared CPU game tests in our data. For rendering, compiling, streaming, and heavier multitasking, Core i7-6660U pulls ahead with 1.2% better PassMark.

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

For streaming, content creation, and heavier multitasking, Core i7-6660U is the stronger fit. You are getting 1.2% better PassMark, backed by 2 cores and 4 threads.

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

Core i7-6660U is still the much better call for a fresh build. Core i7-6660U comes in at an unclear MSRP at unclear MSRP versus $92 MSRP, and it still gives you 1.2% better PassMark. Athlon II X4 651 only looks stronger on raw value math because it is extremely cheap, but that usually means used-market pricing on an obsolete 2011 platform. Even with 100.0% better value on paper (39.0 vs 0.0 PassMark/$), it really only makes sense as a cheap stopgap or a niche existing-platform option for someone already on FM1.

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

Core i7-6660U makes more sense long term for 2026 and beyond. You are getting a newer CPU generation (2016 vs 2011) and more multi-core headroom with 2 cores / 4 threads instead of 4/4. That extra compute headroom is more likely to matter as games, background tasks, and creator workloads get heavier.

Athlon II X4 651 vs Core i7-6660U Technical Specifications

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

Athlon II X4 651

The Athlon II X4 651 is manufactured by AMD. It was released in 2009-01-01. It is based on the Llano (2011−2012) architecture. It features 4 cores and 4 threads. Base frequency is 3 GHz, with boost up to 3 GHz. L3 cache: 0 kB. L2 cache: 1 MB (per core). Built on 32 nm process technology. Socket: FM1. Thermal design power (TDP): 100 Watt. Memory support: DDR3. Passmark benchmark score: 3,584 points. Launch price was $149.

Core i7-6660U

The Core i7-6660U is manufactured by Intel. It was released in 20 March 2016 (9 years ago). It is based on the Skylake (2015−2016) architecture. It features 2 cores and 4 threads. Base frequency is 2.4 GHz, with boost up to 3.4 GHz. L3 cache: 4 MB. L2 cache: 512 kB. Built on 14 nm process technology. Socket: BGA1356. Thermal design power (TDP): 15 Watt. Memory support: DDR4-2133, LPDDR3-1866, DDR3L-1600. Passmark benchmark score: 3,628 points. Launch price was $415.

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Processing Power

The Athlon II X4 651 packs 4 cores / 4 threads, while the Core i7-6660U offers 2 cores / 4 threads — the Athlon II X4 651 has 2 more cores. Boost clocks reach 3 GHz on the Athlon II X4 651 versus 3.4 GHz on the Core i7-6660U — a 12.5% clock advantage for the Core i7-6660U (base: 3 GHz vs 2.4 GHz). The Athlon II X4 651 uses the Llano (2011−2012) architecture (32 nm), while the Core i7-6660U uses Skylake (2015−2016) (14 nm). In PassMark, the Athlon II X4 651 scores 3,584 against the Core i7-6660U's 3,628 — a 1.2% lead for the Core i7-6660U. L3 cache: 0 kB on the Athlon II X4 651 vs 4 MB on the Core i7-6660U.

Feature	Athlon II X4 651	Core i7-6660U
Cores / Threads	4 / 4+100%	2 / 4
Boost Clock	3 GHz	3.4 GHz+13%
Base Clock	3 GHz+25%	2.4 GHz
L3 Cache	0 kB	4 MB
L2 Cache	1 MB (per core)+100%	512 kB
Process	32 nm	14 nm-56%
Architecture	Llano (2011−2012)	Skylake (2015−2016)
PassMark	3,584	3,628+1%

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Memory & Platform

The Athlon II X4 651 uses the FM1 socket (PCIe 2.0), while the Core i7-6660U uses BGA1356 (PCIe 3.0) — making them incompatible on the same motherboard.