Athlon II X4 645 vs Core i5-661

Athlon II X4 645 vs Core i5-661 Performance Spectrum

Athlon II X4 645

4 / 4

2,375

0.0%

Ryzen Threadripper PRO 7955WX

Ryzen Threadripper 3990X

Core i5-661

2 / 4

2,387

+0.5%

Pentium Dual Core T4500

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 645 vs Core i5-661 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 645 vs Core i5-661: 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 645

2010

Why buy it

✅Costs $70 less on MSRP ($126 MSRP vs $196 MSRP).
✅Delivers 54.8% more PassMark for each dollar spent, at 18.8 vs 12.2 PassMark/$ ($126 MSRP vs $196 MSRP).
✅100+% more PCIe lanes (16 vs 0) for storage and expansion-heavy builds.
✅Includes a boxed cooler (Yes), unlike Core i5-661.

Trade-offs

❌Lower PassMark (2,375 vs 2,387).

Core i5-661

2010

Why buy it

✅Draws 87W instead of 95W, a 8W reduction.

Trade-offs

❌Lower PassMark per dollar, at 12.2 vs 18.8 PassMark/$ ($196 MSRP vs $126 MSRP).
❌No boxed cooler included, unlike Athlon II X4 645.

Quick Answers

So, is Core i5-661 better than Athlon II X4 645?

Yes. Core i5-661 is the better all-around CPU here. It gives you a 1.4% average FPS lead across 50 shared CPU game tests in our data and 0.5% better PassMark, which is enough to make it the stronger overall pick.

Which one is better for gaming?

If gaming is the priority, Core i5-661 is the better pick. According to our tests, it delivers 1.4% 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, Core i5-661 is the stronger fit. You are getting 0.5% better PassMark, backed by 2 cores and 4 threads.

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

Core i5-661 is still the much better call for a fresh build. Core i5-661 comes in 55.6% more expensive on MSRP at $196 MSRP versus $126 MSRP, and it still gives you a 1.4% average FPS lead across 50 shared CPU game tests in our data. Athlon II X4 645 only looks stronger on raw value math because it is extremely cheap, but that usually means used-market pricing on an obsolete 2010 platform. Even with 54.8% better value on paper (18.8 vs 12.2 PassMark/$), it really only makes sense as a cheap stopgap or a niche existing-platform option for someone already on AM3.

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

Core i5-661 is the safer long-term CPU choice because it gives you more room to grow and a better platform outlook.

Athlon II X4 645 vs Core i5-661 Technical Specifications

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

Athlon II X4 645

The Athlon II X4 645 is manufactured by AMD. It was released in 21 September 2010 (15 years ago). It is based on the Propus (2009−2011) architecture. It features 4 cores and 4 threads. Base frequency is 3.1 GHz, with boost up to 3.1 GHz. L3 cache: 0 kB. L2 cache: 512 kB (per core). Built on 45 nm process technology. Socket: AM3. Thermal design power (TDP): 95 Watt. Memory support: DDR3. Passmark benchmark score: 2,375 points. Launch price was $80.

Core i5-661

The Core i5-661 is manufactured by Intel. It was released in 7 January 2010 (15 years ago). It is based on the Clarkdale (2010−2011) architecture. It features 2 cores and 4 threads. Base frequency is 3.33 GHz, with boost up to 3.6 GHz. L3 cache: 4 MB (total). L2 cache: 256 kB (per core). Built on 32 nm process technology. Socket: LGA1156. Thermal design power (TDP): 87 Watt. Memory support: DDR3. Passmark benchmark score: 2,387 points. Launch price was $252.

⚡

Processing Power

The Athlon II X4 645 packs 4 cores / 4 threads, while the Core i5-661 offers 2 cores / 4 threads — the Athlon II X4 645 has 2 more cores. Boost clocks reach 3.1 GHz on the Athlon II X4 645 versus 3.6 GHz on the Core i5-661 — a 14.9% clock advantage for the Core i5-661 (base: 3.1 GHz vs 3.33 GHz). The Athlon II X4 645 uses the Propus (2009−2011) architecture (45 nm), while the Core i5-661 uses Clarkdale (2010−2011) (32 nm). In PassMark, the Athlon II X4 645 scores 2,375 against the Core i5-661's 2,387 — a 0.5% lead for the Core i5-661. L3 cache: 0 kB on the Athlon II X4 645 vs 4 MB (total) on the Core i5-661.

Feature	Athlon II X4 645	Core i5-661
Cores / Threads	4 / 4+100%	2 / 4
Boost Clock	3.1 GHz	3.6 GHz+16%
Base Clock	3.1 GHz	3.33 GHz+7%
L3 Cache	0 kB	4 MB (total)
L2 Cache	512 kB (per core)+100%	256 kB (per core)
Process	45 nm	32 nm-29%
Architecture	Propus (2009−2011)	Clarkdale (2010−2011)
PassMark	2,375	2,387
Cinebench R23 Multi	1,374	—
Geekbench 6 Single	399	—
Geekbench 6 Multi	1,374	—

🧠

Memory & Platform

The Athlon II X4 645 uses the AM3 socket (PCIe 2.0), while the Core i5-661 uses LGA1156 (PCIe 2.0) — making them incompatible on the same motherboard.

Feature	Athlon II X4 645	Core i5-661
Socket	AM3	LGA1156
PCIe Generation	PCIe 2.0	PCIe 2.0
Max RAM Speed	DDR3-1333	—
Max RAM Capacity	16 GB	—
RAM Channels	2	—
ECC Support	No	—
PCIe Lanes	16	—

🔧

Advanced Features

Virtualization: Yes (Athlon II X4 645) / not specified (Core i5-661). Primary use case: Athlon II X4 645 targets Desktop.

Feature	Athlon II X4 645	Core i5-661
Integrated GPU	No	—
AVX-512	No	—
Virtualization	Yes	—
Target Use	Desktop	—

💰

Value Analysis

At launch, the Athlon II X4 645 was priced at $126, while the Core i5-661 came in at $196. On launch pricing ($126 vs $196), Athlon II X4 645 was $70 cheaper. In terms of value on MSRP (PassMark points per dollar), the Athlon II X4 645 delivers 18.8 pts/$ vs 12.2 pts/$ for the Core i5-661 — making the Athlon II X4 645 the 43% better value option.

Feature	Athlon II X4 645	Core i5-661
MSRP	$126-36%	$196
Performance per Dollar	18.8+54%	12.2
Release Date	2010	2010

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