Pentium III 1266S vs Pentium III 1400S

Intel

Pentium III 1266S

1 Cores1 Thrd30 WWMax: 1.27 GHz2001
Similar parts
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VS
Intel

Pentium III 1400S

1 Cores1 Thrd32 WWMax: 1.4 GHz2002
Similar parts
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Pentium III 1266S vs Pentium III 1400S Performance Spectrum

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 III 1266S vs Pentium III 1400S 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 III 1266S vs Pentium III 1400S: Pros, Cons & Final Verdict

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

Pentium III 1266S

2001

Why buy it

    Trade-offs

    • Worse for gaming: lower average FPS than Pentium III 1400S across 50 shared CPU benchmark tests.
    • Lower PassMark (210 vs 228).
    • Lower PassMark per dollar, at 0.6 vs 0.9 PassMark/$ ($369 MSRP vs $250 MSRP).
    • No boxed cooler included, unlike Pentium III 1400S.

    Pentium III 1400S

    2002

    Why buy it

    • Better for gaming: +20.0% higher average FPS across 50 shared CPU benchmark tests.
    • Costs $119 less on MSRP ($250 MSRP vs $369 MSRP).
    • Delivers 60.3% more PassMark for each dollar spent, at 0.9 vs 0.6 PassMark/$ ($250 MSRP vs $369 MSRP).
    • Includes a boxed cooler (Yes), unlike Pentium III 1266S.

    Trade-offs

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

    Quick Answers

    So, is Pentium III 1400S better than Pentium III 1266S?
    Yes. Pentium III 1400S is the better all-around CPU here. It gives you a 20.0% average FPS lead across 50 shared CPU game tests in our data, 8.6% 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, Pentium III 1400S is the better pick. According to our tests, it delivers 20.0% 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, Pentium III 1400S is the stronger fit. You are getting 8.6% better PassMark, backed by 1 cores and 1 threads.
    Which one is the smarter buy today, not just the cheaper CPU?
    Pentium III 1400S is the better buy right now. Pentium III 1400S comes in $119 cheaper on MSRP at $250 MSRP versus $369 MSRP, and it still gives you a 20.0% average FPS lead across 50 shared CPU game tests in our data. It is also 60.3% better value on MSRP (0.9 vs 0.6 PassMark/$), so you are getting the faster CPU without taking a value hit on paper.
    Which one is more future-proof for 2026 and beyond?
    Pentium III 1400S makes more sense long term for 2026 and beyond. You are getting a newer CPU generation (2002 vs 2001) 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.

    Pentium III 1266S vs Pentium III 1400S Technical Specifications

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

    Intel

    Pentium III 1266S

    The Pentium III 1266S is manufactured by Intel. It was released in 2007-01-01. It is based on the Tualatin (2000−2002) architecture. It features 1 cores and 1 threads. Max frequency: 1.27 GHz. L3 cache: 0 kB. L2 cache: 512 kB. Built on 130 nm process technology. Socket: PGA370. Thermal design power (TDP): 30 Watt. Passmark benchmark score: 210 points. Launch price was $69.

    Intel

    Pentium III 1400S

    The Pentium III 1400S is manufactured by Intel. It was released in 2007-01-01. It is based on the Tualatin (2000−2002) architecture. It features 1 cores and 1 threads. Max frequency: 1.4 GHz. L3 cache: 0 kB. L2 cache: 512 kB. Built on 130 nm process technology. Socket: PGA370. Thermal design power (TDP): 32 Watt. Passmark benchmark score: 228 points. Launch price was $69.

    Processing Power

    Both the Pentium III 1266S and Pentium III 1400S share an identical 1-core/1-thread configuration. Boost clocks reach 1.27 GHz on the Pentium III 1266S versus 1.4 GHz on the Pentium III 1400S — a 9.7% clock advantage for the Pentium III 1400S. Both are built on the Tualatin (2000−2002) architecture using a 130 nm process. In PassMark, the Pentium III 1266S scores 210 against the Pentium III 1400S's 228 — a 8.2% lead for the Pentium III 1400S. Both processors carry 0 kB of L3 cache.

    FeaturePentium III 1266SPentium III 1400S
    Cores / Threads
    1 / 1
    1 / 1
    Boost Clock
    1.27 GHz
    1.4 GHz+10%
    L3 Cache
    0 kB
    0 kB
    L2 Cache
    512 kB
    512 kB
    Process
    130 nm
    130 nm
    Architecture
    Tualatin (2000−2002)
    Tualatin (2000−2002)
    PassMark
    210
    228+9%
    🧠

    Memory & Platform

    Both processors use the PGA370 socket with PCIe 1.1.

    FeaturePentium III 1266SPentium III 1400S
    Socket
    PGA370
    PGA370
    PCIe Generation
    PCIe 1.1
    PCIe 1.1
    Max RAM Speed
    PC133
    Max RAM Capacity
    4 GB
    RAM Channels
    1
    ECC Support
    Yes
    PCIe Lanes
    0
    🔧

    Advanced Features

    Virtualization: not specified (Pentium III 1266S) / No (Pentium III 1400S).

    FeaturePentium III 1266SPentium III 1400S
    Integrated GPU
    No
    AVX-512
    No
    Virtualization
    No
    💰

    Value Analysis

    At launch, the Pentium III 1266S was priced at $369, while the Pentium III 1400S came in at $250. On launch pricing ($369 vs $250), Pentium III 1400S was $119 cheaper. In terms of value on MSRP (PassMark points per dollar), the Pentium III 1266S delivers 0.6 pts/$ vs 0.9 pts/$ for the Pentium III 1400S — making the Pentium III 1400S the 46.3% better value option.

    FeaturePentium III 1266SPentium III 1400S
    MSRP
    $369
    $250-32%
    Performance per Dollar
    0.6
    0.9+50%
    Release Date
    2001
    2002

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