Pentium 4405U vs Phenom II X4 820

Pentium 4405U vs Phenom II X4 820 Performance Spectrum

Pentium 4405U

2 / 4

2,122

+0.4%

2,114

0.0%

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.

Pentium 4405U vs Phenom II X4 820 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.

Pentium 4405U vs Phenom II X4 820: Pros, Cons & Final Verdict

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

Pentium 4405U

2015

Why buy it

✅+0.4% higher PassMark.

Trade-offs

❌Smaller total L3 cache (2 MB vs 4 MB).
❌438.9% higher power demand at 512W vs 95W.

Phenom II X4 820

2009

Why buy it

✅+100% larger total L3 cache (4 MB vs 2 MB).
✅Draws 95W instead of 512W, a 417W reduction.

Trade-offs

❌Lower PassMark (2,114 vs 2,122).
❌Launch MSRP is still $150 MSRP, while Pentium 4405U mostly shows up through inconsistent older-market listings.

Quick Answers

So, is Phenom II X4 820 better than Pentium 4405U?

It depends on what you want from the system. For gaming, Phenom II X4 820 is ahead with a 1.3% average FPS lead across 48 shared CPU game tests in our data. For rendering, compiling, streaming, and heavier multitasking, Pentium 4405U pulls ahead with 0.4% better PassMark. Phenom II X4 820 also has the bigger cache pool with 100% larger total L3 cache (4 MB vs 2 MB).

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

For streaming, content creation, and heavier multitasking, Pentium 4405U is the stronger fit. You are getting 0.4% better PassMark, backed by 2 cores and 4 threads.

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

Phenom II X4 820 is the better buy right now. Phenom II X4 820 comes in at an unclear MSRP at $150 MSRP versus unclear MSRP, and it still gives you a 1.3% average FPS lead across 48 shared CPU game tests in our data. The compromise is that Pentium 4405U is still stronger for heavier multi-core work with 0.4% better PassMark. It is also 100.0% better value on MSRP (14.1 vs 0.0 PassMark/$), so you are getting the faster CPU without taking a value hit on paper.

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

Pentium 4405U makes more sense long term for 2026 and beyond. You are getting a newer CPU generation (2015 vs 2009) and more multi-core headroom with 2 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.

Pentium 4405U vs Phenom II X4 820 Technical Specifications

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

Pentium 4405U

The Pentium 4405U is manufactured by Intel. It was released in 1 September 2015 (10 years ago). It is based on the NetBurst (2000−2006) architecture. It features 2 cores and 4 threads. Base frequency is 2.1 GHz, with boost up to 2.1 GHz. L3 cache: 2 MB. L2 cache: 512 kB. Built on 14 nm process technology. Socket: BGA1356. Thermal design power (TDP): 15 Watt. Memory support: DDR3, DDR4. Passmark benchmark score: 2,122 points. Launch price was $161.

Phenom II X4 820

The Phenom II X4 820 is manufactured by AMD. It was released in 1 September 2009 (16 years ago). It is based on the Deneb (2009−2011) architecture. It features 4 cores and 4 threads. Base frequency is 2.8 GHz, with boost up to 2.8 GHz. L3 cache: 4 MB (total). 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: 2,114 points. Launch price was $90.

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Processing Power

The Pentium 4405U packs 2 cores / 4 threads, while the Phenom II X4 820 offers 4 cores / 4 threads — the Phenom II X4 820 has 2 more cores. Boost clocks reach 2.1 GHz on the Pentium 4405U versus 2.8 GHz on the Phenom II X4 820 — a 28.6% clock advantage for the Phenom II X4 820 (base: 2.1 GHz vs 2.8 GHz). The Pentium 4405U uses the NetBurst (2000−2006) architecture (14 nm), while the Phenom II X4 820 uses Deneb (2009−2011) (45 nm). In PassMark, the Pentium 4405U scores 2,122 against the Phenom II X4 820's 2,114 — a 0.4% lead for the Pentium 4405U. L3 cache: 2 MB on the Pentium 4405U vs 4 MB (total) on the Phenom II X4 820.

Feature	Pentium 4405U	Phenom II X4 820
Cores / Threads	2 / 4	4 / 4+100%
Boost Clock	2.1 GHz	2.8 GHz+33%
Base Clock	2.1 GHz	2.8 GHz+33%
L3 Cache	2 MB	4 MB (total)+100%
L2 Cache	512 kB	512 kB (per core)
Process	14 nm-69%	45 nm
Architecture	NetBurst (2000−2006)	Deneb (2009−2011)
PassMark	2,122	2,114

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Memory & Platform

The Pentium 4405U uses the BGA1356 socket (PCIe 3.0), while the Phenom II X4 820 uses AM3 (PCIe 2.0) — making them incompatible on the same motherboard.