Athlon II X4 638 vs Athlon II X4 640

Athlon II X4 638 vs Athlon II X4 640 Performance Spectrum

Athlon II X4 638

4 / 4

2,260

0.0%

Ryzen Threadripper PRO 7955WX

Ryzen Threadripper 3990X

Athlon II X4 640

4 / 4

2,266

+0.3%

Ryzen Threadripper PRO 7955WX

Ryzen Threadripper 3990X

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 638 vs Athlon II X4 640 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 638 vs Athlon II X4 640: 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 638

2012

Why buy it

✅Draws 65W instead of 95W, a 30W reduction.

Trade-offs

❌Lower PassMark (2,260 vs 2,266).
❌Lower PassMark per dollar, at 7.5 vs 28.3 PassMark/$ ($300 MSRP vs $80 MSRP).
❌No boxed cooler included, unlike Athlon II X4 640.

Athlon II X4 640

2010

Why buy it

✅Costs $220 less on MSRP ($80 MSRP vs $300 MSRP).
✅Delivers 276.0% more PassMark for each dollar spent, at 28.3 vs 7.5 PassMark/$ ($80 MSRP vs $300 MSRP).
✅Includes a boxed cooler (Yes), unlike Athlon II X4 638.

Trade-offs

❌46.2% higher power demand at 95W vs 65W.

Quick Answers

So, is Athlon II X4 640 better than Athlon II X4 638?

Yes. Athlon II X4 640 is the better all-around CPU here. It gives you a 2.7% average FPS lead across 50 shared CPU game tests in our data and 0.3% better PassMark, which is enough to make it the stronger overall pick.

Which one is better for gaming?

If gaming is the priority, Athlon II X4 640 is the better pick. According to our tests, it delivers 2.7% 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, Athlon II X4 640 is the stronger fit. You are getting 0.3% better PassMark, backed by 4 cores and 4 threads.

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

Athlon II X4 640 is the better buy right now. Athlon II X4 640 comes in $220 cheaper on MSRP at $80 MSRP versus $300 MSRP, and it still gives you a 2.7% average FPS lead across 50 shared CPU game tests in our data. It is also 276.0% better value on MSRP (28.3 vs 7.5 PassMark/$), so you are getting the faster CPU without taking a value hit on paper.

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

Athlon II X4 638 makes more sense long term for 2026 and beyond. You are getting a newer CPU generation (2012 vs 2010). That makes it the safer long-term bet.

Athlon II X4 638 vs Athlon II X4 640 Technical Specifications

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

Athlon II X4 638

The Athlon II X4 638 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 2.7 GHz, with boost up to 2.7 GHz. L3 cache: 0 kB. L2 cache: 1 MB (per core). Built on 32 nm process technology. Socket: FM1. Thermal design power (TDP): 65 Watt. Memory support: DDR3. Passmark benchmark score: 2,260 points. Launch price was $149.

Athlon II X4 640

The Athlon II X4 640 is manufactured by AMD. It was released in 11 May 2010 (15 years ago). It is based on the Propus (2009−2011) 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: 512 kB (per core). Built on 45 nm process technology. Socket: AM3. Thermal design power (TDP): 95 Watt. Memory support: DDR3. Passmark benchmark score: 2,266 points. Launch price was $80.

⚡

Processing Power

Both the Athlon II X4 638 and Athlon II X4 640 share an identical 4-core/4-thread configuration. Boost clocks reach 2.7 GHz on the Athlon II X4 638 versus 3 GHz on the Athlon II X4 640 — a 10.5% clock advantage for the Athlon II X4 640 (base: 2.7 GHz vs 3 GHz). The Athlon II X4 638 uses the Llano (2011−2012) architecture (32 nm), while the Athlon II X4 640 uses Propus (2009−2011) (45 nm). In PassMark, the Athlon II X4 638 scores 2,260 against the Athlon II X4 640's 2,266 — a 0.3% lead for the Athlon II X4 640. Both processors carry 0 kB of L3 cache.

Feature	Athlon II X4 638	Athlon II X4 640
Cores / Threads	4 / 4	4 / 4
Boost Clock	2.7 GHz	3 GHz+11%
Base Clock	2.7 GHz	3 GHz+11%
L3 Cache	0 kB	0 kB
L2 Cache	1 MB (per core)+100%	512 kB (per core)
Process	32 nm-29%	45 nm
Architecture	Llano (2011−2012)	Propus (2009−2011)
PassMark	2,260	2,266
Cinebench R23 Multi	—	1,471
Geekbench 6 Single	—	386
Geekbench 6 Multi	—	1,332

🧠

Memory & Platform

The Athlon II X4 638 uses the FM1 socket (PCIe 2.0), while the Athlon II X4 640 uses AM3 (PCIe 2.0) — making them incompatible on the same motherboard. Maximum memory speed reaches DDR3-1866 on the Athlon II X4 638 versus DDR3-1333 on the Athlon II X4 640 — the Athlon II X4 638 supports 40% faster memory, which can translate to measurable gains in memory-sensitive workloads. The Athlon II X4 638 supports up to 64 GB of RAM compared to 16 GB — 300% more capacity for professional workloads. Both feature 2-channel memory with ECC support. Both provide 16 PCIe lanes. Chipset compatibility: AMD FM1 (Athlon II X4 638) and AM2+,AM3 (Athlon II X4 640).

Feature	Athlon II X4 638	Athlon II X4 640
Socket	FM1	AM3
PCIe Generation	PCIe 2.0	PCIe 2.0
Max RAM Speed	DDR3-1866+40%	DDR3-1333
Max RAM Capacity	64 GB+300%	16 GB
RAM Channels	2	2
ECC Support	No	No
PCIe Lanes	16	16

🔧

Advanced Features

Virtualization: not specified (Athlon II X4 638) / AMD-V (Athlon II X4 640). Primary use case: Athlon II X4 640 targets Budget. Direct competitor: Athlon II X4 640 rivals Core 2 Quad Q8300.

Feature	Athlon II X4 638	Athlon II X4 640
Integrated GPU	No	No
Unlocked	—	No
AVX-512	—	No
Virtualization	—	AMD-V
Target Use	—	Budget

💰

Value Analysis

At launch, the Athlon II X4 638 was priced at $300, while the Athlon II X4 640 came in at $80. On launch pricing ($300 vs $80), Athlon II X4 640 was $220 cheaper. In terms of value on MSRP (PassMark points per dollar), the Athlon II X4 638 delivers 7.5 pts/$ vs 28.3 pts/$ for the Athlon II X4 640 — making the Athlon II X4 640 the 116% better value option.

Feature	Athlon II X4 638	Athlon II X4 640
MSRP	$300	$80-73%
Performance per Dollar	7.5	28.3+277%
Release Date	2012	2010

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