Athlon II X4 635 vs Athlon II X4 638
Athlon II X4 635
Athlon II X4 638
Performance Spectrum - CPU
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.
Value Upgrade Path
This is the official ChipVERSUS Value Rating, comparing raw performance (PassMark) per dollar. Components placed above yours deliver better value for money. The Athlon II X4 635 is positioned at rank 1069 and the Athlon II X4 638 is on rank 1040, so the Athlon II X4 638 offers better cost-efficiency for playing games.
Avg price is the current average price collected from markets across the web.
Performance Per Dollar Athlon II X4 635
Performance Per Dollar Athlon II X4 638
Performance Comparison
About PassMark🏆 Chipversus Verdict
🚀 Performance Leadership
| Insight | Athlon II X4 635 | Athlon II X4 638 |
|---|---|---|
| Gaming | ✅ Superior gaming performance | ❌ Lower gaming performance |
| Workstation | ❌ Weaker in multi-core tasks | ✅ Better multi-core power |
| Price | ✅ More affordable ($250) | ⚠️ Higher cost ($280) |
| Longevity | 🛑 Legacy (Propus (2009−2011) / 45 nm) | 🛑 Legacy (Llano (2011−2012) / 32 nm) |
💎 Value Proposition
| Insight | Athlon II X4 635 | Athlon II X4 638 |
|---|---|---|
| Cost Efficiency | ✅ Better overall value (+11%) | ❌ Lower cost efficiency |
| Upfront Cost | ✅ More affordable ($250) | ⚠️ Higher cost ($280) |
Performance Check
To accurately isolate CPU performance, all benchmarks below use an NVIDIA RTX 4090 as the reference GPU. This eliminates GPU-side bottlenecks and highlights pure processing throughput differences between the CPUs.
Note: Real-world results may vary based on your actual GPU. CPU performance impact is more visible in processing-intensive titles and high-refresh-rate gaming scenarios.
Technical Specifications
Side-by-side comparison of Athlon II X4 635 and Athlon II X4 638
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. Both support up to DDR3-1333 / DDR2-1066 memory speed. The Athlon II X4 638 supports up to 64 GB of RAM compared to 16 GB — 120% 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 |
| Max RAM Capacity | 16 GB | 64 GB+300% |
| RAM Channels | 2 | 2 |
| ECC Support | ❌ | ❌ |
| 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
The Athlon II X4 635 launched at $400 MSRP, while the Athlon II X4 638 debuted at $300. At current prices ($250 vs $280), the Athlon II X4 635 is $30 cheaper. In terms of value (PassMark points per dollar), the Athlon II X4 635 delivers 9.0 pts/$ vs 8.1 pts/$ for the Athlon II X4 638 — making the Athlon II X4 635 the 10.8% better value option.
| Feature | Athlon II X4 635 | Athlon II X4 638 |
|---|---|---|
| MSRP | $400 | $300-25% |
| Avg Price (30d) | $250-11% | $280 |
| Performance per Dollar | 9.0+11% | 8.1 |
| Release Date | 2010 | 2012 |
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