Core i3-8109U vs Core i3-8121U

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 i3-8109U vs Core i3-8121U 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 i3-8109U vs Core i3-8121U: Pros, Cons & Final Verdict

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

Core i3-8109U

2018

Why buy it

✅Integrated graphics onboard with Iris Plus Graphics 655, while Core i3-8121U needs a discrete GPU.

Trade-offs

❌Lower Geekbench single-core performance for gaming (1,100 vs 1,178).
❌Lower PassMark (4,184 vs 4,271).
❌86.7% higher power demand at 28W vs 15W.

Core i3-8121U

2018

Why buy it

✅+7.1% higher Geekbench single-core performance for gaming and desktop responsiveness.
✅Draws 15W instead of 28W, a 13W reduction.

Trade-offs

❌No integrated graphics, while Core i3-8109U can still boot and troubleshoot without a discrete GPU.

Quick Answers

So, is Core i3-8121U better than Core i3-8109U?

Yes. Core i3-8121U is the better all-around CPU here. It gives you a 1.0% average FPS lead across 50 shared CPU game tests in our data, 2.1% 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, Core i3-8121U is the better pick. According to our tests, it delivers 1.0% 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, Core i3-8121U is the stronger fit. You are getting 2.1% better PassMark, backed by 2 cores and 4 threads.

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

Core i3-8121U still makes the most sense overall. Core i3-8121U comes in at an unclear MSRP at unclear MSRP versus unclear MSRP, and it still gives you a 1.0% average FPS lead across 50 shared CPU game tests in our data.

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

Core i3-8121U makes more sense long term for 2026 and beyond. You are getting more multi-core headroom with 2 cores / 4 threads instead of 2/4. That extra compute headroom is more likely to matter as games, background tasks, and creator workloads get heavier.

Core i3-8109U vs Core i3-8121U Technical Specifications

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

Core i3-8109U

The Core i3-8109U is manufactured by Intel. It was released in 5 April 2018 (7 years ago). It is based on the Coffee Lake-U (2018−2019) architecture. It features 2 cores and 4 threads. Base frequency is 3 GHz, with boost up to 3.6 GHz. L3 cache: 4 MB (total). L2 cache: 256K (per core). Built on 14 nm process technology. Socket: FCBGA1528. Thermal design power (TDP): 28 Watt. Memory support: DDR4. Passmark benchmark score: 4,184 points. Launch price was $304.

Core i3-8121U

The Core i3-8121U is manufactured by Intel. It was released in 5 May 2018 (7 years ago). It is based on the Coffee Lake-U (2018−2019) architecture. It features 2 cores and 4 threads. Base frequency is 2.2 GHz, with boost up to 3.2 GHz. L3 cache: 4 MB (total). L2 cache: 256K (per core). Built on 10 nm process technology. Socket: BGA1440. Thermal design power (TDP): 15 Watt. Memory support: DDR4. Passmark benchmark score: 4,271 points. Launch price was $69.

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Processing Power

Both the Core i3-8109U and Core i3-8121U share an identical 2-core/4-thread configuration. Boost clocks reach 3.6 GHz on the Core i3-8109U versus 3.2 GHz on the Core i3-8121U — a 11.8% clock advantage for the Core i3-8109U (base: 3 GHz vs 2.2 GHz). Both are built on the Coffee Lake-U (2018−2019) architecture using a 14 nm process. In PassMark, the Core i3-8109U scores 4,184 against the Core i3-8121U's 4,271 — a 2.1% lead for the Core i3-8121U. Geekbench 6 single-core — the metric most relevant to gaming — records 1,100 vs 1,178, a 6.8% lead for the Core i3-8121U that directly translates to higher frame rates. Both processors carry 4 MB (total) of L3 cache.

Feature	Core i3-8109U	Core i3-8121U
Cores / Threads	2 / 4	2 / 4
Boost Clock	3.6 GHz+12%	3.2 GHz
Base Clock	3 GHz+36%	2.2 GHz
L3 Cache	4 MB (total)	4 MB (total)
L2 Cache	256K (per core)	256K (per core)
Process	14 nm	10 nm-29%
Architecture	Coffee Lake-U (2018−2019)	Coffee Lake-U (2018−2019)
PassMark	4,184	4,271+2%
Geekbench 6 Single	1,100	1,178+7%
Geekbench 6 Multi	—	2,250

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Memory & Platform

The Core i3-8109U uses the FCBGA1528 socket (PCIe 3.0), while the Core i3-8121U uses BGA1440 (PCIe 3.0) — making them incompatible on the same motherboard. Both support up to DDR4-2400 memory speed. Both support up to 32 GB of RAM. Both feature 2-channel memory with ECC support. Both provide 16 PCIe lanes.

Feature	Core i3-8109U	Core i3-8121U
Socket	FCBGA1528	BGA1440
PCIe Generation	PCIe 3.0	PCIe 3.0
Max RAM Speed	DDR4-2400	DDR4-2400
Max RAM Capacity	32 GB	32 GB
RAM Channels	2	2
ECC Support	No	No
PCIe Lanes	16	16

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Advanced Features

Neither processor supports overclocking. Only the Core i3-8121U supports AVX-512 instructions — important for machine learning and scientific applications. Both support VT-x, VT-d, EPT virtualization. The Core i3-8109U includes integrated graphics (Iris Plus Graphics 655), while the Core i3-8121U requires a dedicated GPU. Primary use case: Core i3-8109U targets Performance Laptop, Core i3-8121U targets Productivity. Direct competitor: Core i3-8109U rivals Ryzen 3 3200U; Core i3-8121U rivals Core i3-8130U.

Feature	Core i3-8109U	Core i3-8121U
Integrated GPU	Yes	No
IGPU Model	Iris Plus Graphics 655	—
Unlocked	No	No
AVX-512	No	Yes
Virtualization	VT-x, VT-d, EPT	VT-x, VT-d, EPT
Target Use	Performance Laptop	Productivity