Athlon II X4 635 vs Athlon II X4 638

Athlon II X4 635 vs Athlon II X4 638 Performance Spectrum

Athlon II X4 635

4 / 4

2,248

0.0%

Ryzen Threadripper PRO 7955WX

Ryzen Threadripper 3990X

Athlon II X4 638

4 / 4

2,260

+0.5%

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 635 vs Athlon II X4 638 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 635 vs Athlon II X4 638: 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 635

2010

Why buy it

✅Includes a boxed cooler (Yes), unlike Athlon II X4 638.

Trade-offs

❌Lower PassMark (2,248 vs 2,260).
❌Lower PassMark per dollar, at 5.6 vs 7.5 PassMark/$ ($400 MSRP vs $300 MSRP).
❌46.2% higher power demand at 95W vs 65W.

Athlon II X4 638

2012

Why buy it

✅+0.5% higher PassMark.
✅Costs $100 less on MSRP ($300 MSRP vs $400 MSRP).
✅Delivers 34.0% more PassMark for each dollar spent, at 7.5 vs 5.6 PassMark/$ ($300 MSRP vs $400 MSRP).
✅Draws 65W instead of 95W, a 30W reduction.

Trade-offs

❌No boxed cooler included, unlike Athlon II X4 635.

Quick Answers

So, is Athlon II X4 638 better than Athlon II X4 635?

It depends on what you want from the system. For gaming, Athlon II X4 635 is ahead with a 0.1% average FPS lead across 28 shared CPU game tests in our data. For rendering, compiling, streaming, and heavier multitasking, Athlon II X4 638 pulls ahead with 0.5% better PassMark.

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

For streaming, content creation, and heavier multitasking, Athlon II X4 638 is the stronger fit. You are getting 0.5% better PassMark, backed by 4 cores and 4 threads.

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

Athlon II X4 638 is the better buy right now. Athlon II X4 638 comes in $100 cheaper on MSRP at $300 MSRP versus $400 MSRP, and it still gives you 0.5% better PassMark. The compromise is that Athlon II X4 635 is still the better pure gaming CPU with a 0.1% average FPS lead across 28 shared CPU game tests in our data. It is also 34.0% better value on MSRP (7.5 vs 5.6 PassMark/$), 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) and more multi-core headroom with 4 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 635 vs Athlon II X4 638 Technical Specifications

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

Athlon II X4 635

The Athlon II X4 635 is manufactured by AMD. It was released in 25 January 2010 (15 years ago). It is based on the Propus (2009−2011) architecture. It features 4 cores and 4 threads. Base frequency is 2.9 GHz, with boost up to 2.9 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: 2,248 points. Launch price was $70.

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.

⚡

Processing Power

Both the Athlon II X4 635 and Athlon II X4 638 share an identical 4-core/4-thread configuration. Boost clocks reach 2.9 GHz on the Athlon II X4 635 versus 2.7 GHz on the Athlon II X4 638 — a 7.1% clock advantage for the Athlon II X4 635 (base: 2.9 GHz vs 2.7 GHz). The Athlon II X4 635 uses the Propus (2009−2011) architecture (45 nm), while the Athlon II X4 638 uses Llano (2011−2012) (32 nm). In PassMark, the Athlon II X4 635 scores 2,248 against the Athlon II X4 638's 2,260 — a 0.5% lead for the Athlon II X4 638. Both processors carry 0 kB of L3 cache.

Feature	Athlon II X4 635	Athlon II X4 638
Cores / Threads	4 / 4	4 / 4
Boost Clock	2.9 GHz+7%	2.7 GHz
Base Clock	2.9 GHz+7%	2.7 GHz
L3 Cache	0 kB	0 kB
L2 Cache	512 kB (per core)	1 MB (per core)+100%
Process	45 nm	32 nm-29%
Architecture	Propus (2009−2011)	Llano (2011−2012)
PassMark	2,248	2,260
Cinebench R23 Multi	658	—
Geekbench 6 Single	180	—
Geekbench 6 Multi	550	—

🧠

Memory & Platform

The Athlon II X4 635 uses the AM3 socket (PCIe 2.0), while the Athlon II X4 638 uses FM1 (PCIe 2.0) — making them incompatible on the same motherboard. Maximum memory speed reaches DDR3-1333 / DDR2-1066 on the Athlon II X4 635 versus DDR3-1866 on the Athlon II X4 638 — 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 770,785G,790FX,880G,890FX,970,990FX (Athlon II X4 635) and AMD FM1 (Athlon II X4 638).

Feature	Athlon II X4 635	Athlon II X4 638
Socket	AM3	FM1
PCIe Generation	PCIe 2.0	PCIe 2.0
Max RAM Speed	DDR3-1333 / DDR2-1066	DDR3-1866+40%
Max RAM Capacity	16 GB	64 GB+300%
RAM Channels	2	2
ECC Support	No	No
PCIe Lanes	16	16

🔧

Advanced Features

Virtualization: AMD-V (Athlon II X4 635) / not specified (Athlon II X4 638). Primary use case: Athlon II X4 635 targets Budget.

Feature	Athlon II X4 635	Athlon II X4 638
Integrated GPU	No	No
Unlocked	Yes	—
AVX-512	No	—
Virtualization	AMD-V	—
Target Use	Budget	—

💰

Value Analysis

At launch, the Athlon II X4 635 was priced at $400, while the Athlon II X4 638 came in at $300. On launch pricing ($400 vs $300), Athlon II X4 638 was $100 cheaper. In terms of value on MSRP (PassMark points per dollar), the Athlon II X4 635 delivers 5.6 pts/$ vs 7.5 pts/$ for the Athlon II X4 638 — making the Athlon II X4 638 the 29.1% better value option.

Feature	Athlon II X4 635	Athlon II X4 638
MSRP	$400	$300-25%
Performance per Dollar	5.6	7.5+34%
Release Date	2010	2012

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