Atom N455 vs Mobile Sempron SI-42

Atom N455 vs Mobile Sempron SI-42 Performance Spectrum

Atom N455

1 / 2

345

+3.9%

332

0.0%

Ryzen Threadripper PRO 3955WX

Ryzen Threadripper PRO 7955WX

Ryzen Threadripper 3990X

Ryzen Threadripper 7970X

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.

Atom N455 vs Mobile Sempron SI-42 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.

Atom N455 vs Mobile Sempron SI-42: Pros, Cons & Final Verdict

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

Atom N455

2010

Why buy it

✅Better for gaming: +12.3% higher average FPS across 50 shared CPU benchmark tests.
✅Integrated graphics onboard with Intel GMA 3150, while Mobile Sempron SI-42 needs a discrete GPU.

Trade-offs

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

Mobile Sempron SI-42

2009

Why buy it

Trade-offs

❌Worse for gaming: lower average FPS than Atom N455 across 50 shared CPU benchmark tests.
❌Lower PassMark (332 vs 345).
❌No integrated graphics, while Atom N455 can still boot and troubleshoot without a discrete GPU.

Quick Answers

So, is Atom N455 better than Mobile Sempron SI-42?

Yes. Atom N455 is the better all-around CPU here. It gives you a 12.3% average FPS lead across 50 shared CPU game tests in our data, 3.9% 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, Atom N455 is the better pick. According to our tests, it delivers 12.3% 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, Atom N455 is the stronger fit. You are getting 3.9% better PassMark, backed by 1 cores and 2 threads.

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

Atom N455 still makes the most sense overall. Atom N455 comes in at an unclear MSRP at unclear MSRP versus unclear MSRP, and it still gives you a 12.3% average FPS lead across 50 shared CPU game tests in our data.

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

Atom N455 makes more sense long term for 2026 and beyond. You are getting a newer CPU generation (2010 vs 2009) and more multi-core headroom with 1 cores / 2 threads instead of 1/1. That extra compute headroom is more likely to matter as games, background tasks, and creator workloads get heavier.

Atom N455 vs Mobile Sempron SI-42 Technical Specifications

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

Atom N455

The Atom N455 is manufactured by Intel. It was released in 1 June 2010 (15 years ago). It is based on the Pinetrail (2009−2011) architecture. It features 1 cores and 2 threads. Base frequency is 1.66 GHz, with boost up to 1.67 GHz. L3 cache: 0 kB. L2 cache: 512K (per core). Built on 45 nm process technology. Socket: FCBGA559. Thermal design power (TDP): 6.5 Watt. Memory support: DDR3. Passmark benchmark score: 345 points. Launch price was $64.

Mobile Sempron SI-42

The Mobile Sempron SI-42 is manufactured by AMD. It was released in 1 September 2009 (16 years ago). It is based on the Sable (2008−2009) architecture. It features 1 cores and 1 threads. Max frequency: 2.1 GHz. L2 cache: 512 kB. Built on 65 nm process technology. Socket: S1g2. Thermal design power (TDP): 512 kB. Passmark benchmark score: 332 points. Launch price was $69.

⚡

Processing Power

The Atom N455 packs 1 cores / 2 threads, matching the Mobile Sempron SI-42's 1 cores. Boost clocks reach 1.67 GHz on the Atom N455 versus 2.1 GHz on the Mobile Sempron SI-42 — a 22.8% clock advantage for the Mobile Sempron SI-42. The Atom N455 uses the Pinetrail (2009−2011) architecture (45 nm), while the Mobile Sempron SI-42 uses Sable (2008−2009) (65 nm). In PassMark, the Atom N455 scores 345 against the Mobile Sempron SI-42's 332 — a 3.8% lead for the Atom N455.

Feature	Atom N455	Mobile Sempron SI-42
Cores / Threads	1 / 2	1 / 1
Boost Clock	1.67 GHz	2.1 GHz+26%
Base Clock	1.66 GHz	—
L3 Cache	0 kB	—
L2 Cache	512K (per core)	512 kB
Process	45 nm-31%	65 nm
Architecture	Pinetrail (2009−2011)	Sable (2008−2009)
PassMark	345+4%	332

🧠

Memory & Platform

The Atom N455 uses the FCBGA559 socket (PCIe 2.0), while the Mobile Sempron SI-42 uses S1g2 (PCIe 2.0) — making them incompatible on the same motherboard.