Pentium III 1133 vs Pentium III 1266S

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 1133 vs Pentium III 1266S 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 1133 vs Pentium III 1266S: 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 1133

2000

Why buy it

Trade-offs

❌Worse for gaming: lower average FPS than Pentium III 1266S across 50 shared CPU benchmark tests.
❌Lower PassMark (180 vs 210).
❌Lower PassMark per dollar, at 0.2 vs 0.6 PassMark/$ ($990 MSRP vs $369 MSRP).

Pentium III 1266S

2001

Why buy it

✅Better for gaming: +25.0% higher average FPS across 50 shared CPU benchmark tests.
✅Costs $621 less on MSRP ($369 MSRP vs $990 MSRP).
✅Delivers 213.0% more PassMark for each dollar spent, at 0.6 vs 0.2 PassMark/$ ($369 MSRP vs $990 MSRP).

Trade-offs

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

Quick Answers

So, is Pentium III 1266S better than Pentium III 1133?

Yes. Pentium III 1266S is the better all-around CPU here. It gives you a 25.0% average FPS lead across 50 shared CPU game tests in our data, 16.7% 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 1266S is the better pick. According to our tests, it delivers 25.0% 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 1266S is the stronger fit. You are getting 16.7% better PassMark, backed by 1 cores and 1 threads.

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

Pentium III 1266S is the better buy right now. Pentium III 1266S comes in $621 cheaper on MSRP at $369 MSRP versus $990 MSRP, and it still gives you a 25.0% average FPS lead across 50 shared CPU game tests in our data. It is also 213.0% better value on MSRP (0.6 vs 0.2 PassMark/$), 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 1266S makes more sense long term for 2026 and beyond. You are getting a newer CPU generation (2001 vs 2000) 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 1133 vs Pentium III 1266S Technical Specifications

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

Pentium III 1133

The Pentium III 1133 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: 1.13 GHz. L3 cache: 0 kB. L2 cache: 256 kB. Built on 180 nm process technology. Socket: PGA370. Thermal design power (TDP): 29 Watt. Passmark benchmark score: 180 points. Launch price was $69.

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.

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Processing Power

Both the Pentium III 1133 and Pentium III 1266S share an identical 1-core/1-thread configuration. Boost clocks reach 1.13 GHz on the Pentium III 1133 versus 1.27 GHz on the Pentium III 1266S — a 11.7% clock advantage for the Pentium III 1266S. Both are built on the Tualatin (2000−2002) architecture using a 180 nm process. In PassMark, the Pentium III 1133 scores 180 against the Pentium III 1266S's 210 — a 15.4% lead for the Pentium III 1266S. Both processors carry 0 kB of L3 cache.

Feature	Pentium III 1133	Pentium III 1266S
Cores / Threads	1 / 1	1 / 1
Boost Clock	1.13 GHz	1.27 GHz+12%
L3 Cache	0 kB	0 kB
L2 Cache	256 kB	512 kB+100%
Process	180 nm	130 nm-28%
Architecture	Tualatin (2000−2002)	Tualatin (2000−2002)
PassMark	180	210+17%

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Memory & Platform

Both processors use the PGA370 socket with PCIe 1.1.

Feature	Pentium III 1133	Pentium III 1266S
Socket	PGA370	PGA370
PCIe Generation	PCIe 1.1	PCIe 1.1

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Value Analysis

At launch, the Pentium III 1133 was priced at $990, while the Pentium III 1266S came in at $369. On launch pricing ($990 vs $369), Pentium III 1266S was $621 cheaper. In terms of value on MSRP (PassMark points per dollar), the Pentium III 1133 delivers 0.2 pts/$ vs 0.6 pts/$ for the Pentium III 1266S — making the Pentium III 1266S the 103.1% better value option.

Feature	Pentium III 1133	Pentium III 1266S
MSRP	$990	$369-63%
Performance per Dollar	0.2	0.6+200%
Release Date	2000	2001

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