Core 2 Duo T5850 vs Core 2 Quad Q9400

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.

Core 2 Duo T5850 vs Core 2 Quad Q9400 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.

Core 2 Duo T5850 vs Core 2 Quad Q9400: Pros, Cons & Final Verdict

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

Core 2 Duo T5850

2008

Why buy it

✅+0% higher PassMark.
✅Draws 2W instead of 95W, a 93W reduction.

Trade-offs

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

Core 2 Quad Q9400

2008

Why buy it

Trade-offs

❌Lower PassMark (2,160 vs 2,161).
❌Launch MSRP is still $229 MSRP, while Core 2 Duo T5850 mostly shows up through inconsistent older-market listings.
❌4650% higher power demand at 95W vs 2W.

Quick Answers

So, is Core 2 Duo T5850 better than Core 2 Quad Q9400?

It depends on what you want from the system. For gaming, Core 2 Quad Q9400 is ahead with a 0.5% average FPS lead across 50 shared CPU game tests in our data. For rendering, compiling, streaming, and heavier multitasking, Core 2 Duo T5850 pulls ahead with 0% better PassMark.

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

For streaming, content creation, and heavier multitasking, Core 2 Duo T5850 is the stronger fit. You are getting 0% better PassMark, backed by 2 cores and 2 threads.

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

Core 2 Duo T5850 is still the much better call for a fresh build. Core 2 Duo T5850 comes in at an unclear MSRP at unclear MSRP versus $229 MSRP, and it still gives you 0% better PassMark. Core 2 Quad Q9400 only looks stronger on raw value math because it is extremely cheap, but that usually means used-market pricing on an obsolete 2008 platform. Even with 100.0% better value on paper (9.4 vs 0.0 PassMark/$), it really only makes sense as a cheap stopgap or a niche existing-platform option for someone already on LGA775.

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

Core 2 Quad Q9400 is the safer long-term CPU choice because it gives you more room to grow and a better platform outlook.

Core 2 Duo T5850 vs Core 2 Quad Q9400 Technical Specifications

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

Core 2 Duo T5850

The Core 2 Duo T5850 is manufactured by Intel. It was released in 2008-01-01. It is based on the Merom (2006−2008) architecture. It features 2 cores and 2 threads. Max frequency: 2.1 GHz. L2 cache: 2 MB. Built on 65 nm process technology. Thermal design power (TDP): 2 MB. Passmark benchmark score: 2,161 points. Launch price was $249.

Core 2 Quad Q9400

The Core 2 Quad Q9400 is manufactured by Intel. It was released in 2008-01-01. It is based on the Yorkfield (2007−2009) architecture. It features 4 cores and 4 threads. Base frequency is 2.66 GHz, with boost up to 2.67 GHz. L3 cache: 0 kB. L2 cache: 6 MB (total). Built on 45 nm process technology. Socket: LGA775. Thermal design power (TDP): 95 Watt. Memory support: DDR1, DDR2, DDR3. Passmark benchmark score: 2,160 points. Launch price was $249.

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Processing Power

The Core 2 Duo T5850 packs 2 cores / 2 threads, while the Core 2 Quad Q9400 offers 4 cores / 4 threads — the Core 2 Quad Q9400 has 2 more cores. Boost clocks reach 2.1 GHz on the Core 2 Duo T5850 versus 2.67 GHz on the Core 2 Quad Q9400 — a 23.9% clock advantage for the Core 2 Quad Q9400. The Core 2 Duo T5850 uses the Merom (2006−2008) architecture (65 nm), while the Core 2 Quad Q9400 uses Yorkfield (2007−2009) (45 nm). In PassMark, the Core 2 Duo T5850 scores 2,161 against the Core 2 Quad Q9400's 2,160 — a 0% lead for the Core 2 Duo T5850.

Feature	Core 2 Duo T5850	Core 2 Quad Q9400
Cores / Threads	2 / 2	4 / 4+100%
Boost Clock	2.1 GHz	2.67 GHz+27%
Base Clock	—	2.66 GHz
L3 Cache	—	0 kB
L2 Cache	2 MB	6 MB (total)+200%
Process	65 nm	45 nm-31%
Architecture	Merom (2006−2008)	Yorkfield (2007−2009)
PassMark	2,161	2,160