Athlon 64 3800+ vs Athlon 64 FX-51

Athlon 64 3800+ vs Athlon 64 FX-51 Performance Spectrum

Athlon 64 3800+

1 / 1

648

+5.4%

Ryzen Threadripper PRO 3955WX

Ryzen Threadripper PRO 7955WX

Ryzen Threadripper 3990X

Athlon 64 FX-51

1 / 1

615

0.0%

Ryzen Threadripper PRO 3955WX

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 64 3800+ vs Athlon 64 FX-51 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 64 3800+ vs Athlon 64 FX-51: Pros, Cons & Final Verdict

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

Athlon 64 3800+

2004

Why buy it

✅Better for gaming: +6.7% higher average FPS across 50 shared CPU benchmark tests.
✅Costs $379 less on MSRP ($354 MSRP vs $733 MSRP).
✅Delivers 118.2% more PassMark for each dollar spent, at 1.8 vs 0.8 PassMark/$ ($354 MSRP vs $733 MSRP).

Trade-offs

❌Fewer obvious downsides in this matchup outside of normal market pricing swings.

Athlon 64 FX-51

2003

Why buy it

Trade-offs

❌Worse for gaming: lower average FPS than Athlon 64 3800+ across 50 shared CPU benchmark tests.
❌Lower PassMark (615 vs 648).
❌Lower PassMark per dollar, at 0.8 vs 1.8 PassMark/$ ($733 MSRP vs $354 MSRP).

Quick Answers

So, is Athlon 64 3800+ better than Athlon 64 FX-51?

Yes. Athlon 64 3800+ is the better all-around CPU here. It gives you a 6.7% average FPS lead across 50 shared CPU game tests in our data, 5.4% better PassMark, and the stronger long-term platform, which is enough to make it the stronger overall pick.

Which one is better for gaming?

If gaming is the priority, Athlon 64 3800+ is the better pick. According to our tests, it delivers 6.7% 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 64 3800+ is the stronger fit. You are getting 5.4% better PassMark, backed by 1 cores and 1 threads.

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

Athlon 64 3800+ is the better buy right now. Athlon 64 3800+ comes in $379 cheaper on MSRP at $354 MSRP versus $733 MSRP, and it still gives you a 6.7% average FPS lead across 50 shared CPU game tests in our data. It is also 118.2% better value on MSRP (1.8 vs 0.8 PassMark/$), 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 64 3800+ makes more sense long term for 2026 and beyond. You are getting a newer CPU generation (2004 vs 2003) and more multi-core headroom with 1 cores / 1 threads instead of 1/1. That extra compute headroom is more likely to matter as games, background tasks, and creator workloads get heavier.

Athlon 64 3800+ vs Athlon 64 FX-51 Technical Specifications

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

Athlon 64 3800+

The Athlon 64 3800+ is manufactured by AMD. It was released in Junho 2004 (21 years ago). It is based on the Venice (2004−2005) architecture. It features 1 cores and 1 threads. Max frequency: 2.4 GHz. L3 cache: 0 kB. L2 cache: 512 kB. Built on 130 nm process technology. Socket: 939. Thermal design power (TDP): 89 Watt. Memory support: DDR1. Passmark benchmark score: 648 points. Launch price was $160.

Athlon 64 FX-51

The Athlon 64 FX-51 is manufactured by AMD. It was released in 2009-01-01. It is based on the SledgeHammer (2003−2005) architecture. It features 1 cores and 1 threads. Max frequency: 2.2 GHz. L3 cache: 0 kB. L2 cache: 1 MB. Built on 130 nm process technology. Socket: 940. Thermal design power (TDP): 89 Watt. Passmark benchmark score: 615 points. Launch price was $149.

⚡

Processing Power

Both the Athlon 64 3800+ and Athlon 64 FX-51 share an identical 1-core/1-thread configuration. Boost clocks reach 2.4 GHz on the Athlon 64 3800+ versus 2.2 GHz on the Athlon 64 FX-51 — a 8.7% clock advantage for the Athlon 64 3800+. The Athlon 64 3800+ uses the Venice (2004−2005) architecture (130 nm), while the Athlon 64 FX-51 uses SledgeHammer (2003−2005) (130 nm). In PassMark, the Athlon 64 3800+ scores 648 against the Athlon 64 FX-51's 615 — a 5.2% lead for the Athlon 64 3800+. Both processors carry 0 kB of L3 cache.

Feature	Athlon 64 3800+	Athlon 64 FX-51
Cores / Threads	1 / 1	1 / 1
Boost Clock	2.4 GHz+9%	2.2 GHz
L3 Cache	0 kB	0 kB
L2 Cache	512 kB	1 MB+100%
Process	130 nm	130 nm
Architecture	Venice (2004−2005)	SledgeHammer (2003−2005)
PassMark	648+5%	615

🧠

Memory & Platform

The Athlon 64 3800+ uses the 939 socket (PCIe 1.1), while the Athlon 64 FX-51 uses 940 (PCIe 1.1) — making them incompatible on the same motherboard. Maximum memory speed reaches DDR2-800 on the Athlon 64 3800+ versus DDR-400 on the Athlon 64 FX-51 — the Athlon 64 3800+ supports -300% faster memory, which can translate to measurable gains in memory-sensitive workloads. The Athlon 64 3800+ supports up to 16 GB of RAM compared to 4 GB — 300% more capacity for professional workloads. Both feature 2-channel memory with ECC support. Both provide 0 PCIe lanes. Chipset compatibility: AMD AM2 (Athlon 64 3800+) and AMD 940 (Athlon 64 FX-51).

Feature	Athlon 64 3800+	Athlon 64 FX-51
Socket	939	940
PCIe Generation	PCIe 1.1	PCIe 1.1
Max RAM Speed	DDR2-800	DDR-400
Max RAM Capacity	16 GB+300%	4 GB
RAM Channels	2	2
ECC Support	No	Yes
PCIe Lanes	0	0

💰

Value Analysis

At launch, the Athlon 64 3800+ was priced at $354, while the Athlon 64 FX-51 came in at $733. On launch pricing ($354 vs $733), Athlon 64 3800+ was $379 cheaper. In terms of value on MSRP (PassMark points per dollar), the Athlon 64 3800+ delivers 1.8 pts/$ vs 0.8 pts/$ for the Athlon 64 FX-51 — making the Athlon 64 3800+ the 74.3% better value option.

Feature	Athlon 64 3800+	Athlon 64 FX-51
MSRP	$354-52%	$733
Performance per Dollar	1.8+125%	0.8
Release Date	2004	2003

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