Core i5-8279U vs Core i5-8400T

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 i5-8279U vs Core i5-8400T 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 i5-8279U vs Core i5-8400T: Pros, Cons & Final Verdict

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

Core i5-8279U

2019

Why buy it

✅Better for gaming: +18.4% higher average FPS across 50 shared CPU benchmark tests.
✅Draws 28W instead of 35W, a 7W reduction.

Trade-offs

❌Smaller total L3 cache (6 MB vs 9 MB).
❌No integrated graphics, while Core i5-8400T can still boot and troubleshoot without a discrete GPU.
❌No boxed cooler included, unlike Core i5-8400T.

Core i5-8400T

2018

Why buy it

✅+50% larger total L3 cache (9 MB vs 6 MB).
✅100+% more PCIe lanes (16 vs 0) for storage and expansion-heavy builds.
✅Integrated graphics onboard with UHD Graphics 630, while Core i5-8279U needs a discrete GPU.
✅Includes a boxed cooler (Yes), unlike Core i5-8279U.

Trade-offs

❌Worse for gaming: lower average FPS than Core i5-8279U across 50 shared CPU benchmark tests.
❌Lower PassMark (7,426 vs 7,464).
❌Launch MSRP is still $182 MSRP, while Core i5-8279U mostly shows up through inconsistent older-market listings.
❌25% higher power demand at 35W vs 28W.

Quick Answers

So, is Core i5-8279U better than Core i5-8400T?

Yes. Core i5-8279U is the better all-around CPU here. It gives you a 18.4% average FPS lead across 50 shared CPU game tests in our data, 0.5% 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 i5-8279U is the better pick. According to our tests, it delivers 18.4% 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 i5-8279U is the stronger fit. You are getting 0.5% better PassMark, backed by 4 cores and 8 threads.

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

Core i5-8279U is still the much better call for a fresh build. Core i5-8279U comes in at an unclear MSRP at unclear MSRP versus $182 MSRP, and it still gives you a 18.4% average FPS lead across 50 shared CPU game tests in our data. Core i5-8400T only looks stronger on raw value math because it is extremely cheap, but that usually means used-market pricing on an obsolete 2018 platform. Even with 100.0% better value on paper (40.8 vs 0.0 PassMark/$), it really only makes sense as a cheap stopgap or a niche existing-platform option for someone already on LGA1151.

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

Core i5-8279U makes more sense long term for 2026 and beyond. You are getting a newer CPU generation (2019 vs 2018) and more multi-core headroom with 4 cores / 8 threads instead of 6/6. That extra compute headroom is more likely to matter as games, background tasks, and creator workloads get heavier.

Core i5-8279U vs Core i5-8400T Technical Specifications

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

Core i5-8279U

The Core i5-8279U is manufactured by Intel. It was released in 3 April 2019 (6 years ago). It is based on the Coffee Lake-U (2018−2019) architecture. It features 4 cores and 8 threads. Base frequency is 2.4 GHz, with boost up to 4.1 GHz. L3 cache: 6 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: 7,464 points. Launch price was $320.

Core i5-8400T

The Core i5-8400T is manufactured by Intel. It was released in 2 April 2018 (7 years ago). It is based on the Coffee Lake (2017−2019) architecture. It features 6 cores and 6 threads. Base frequency is 1.7 GHz, with boost up to 3.3 GHz. L3 cache: 9 MB (total). L2 cache: 256K (per core). Built on 14 nm process technology. Socket: LGA1151. Thermal design power (TDP): 35 Watt. Memory support: DDR4-2666. Passmark benchmark score: 7,426 points. Launch price was $182.

⚡

Processing Power

The Core i5-8279U packs 4 cores / 8 threads, while the Core i5-8400T offers 6 cores / 6 threads — the Core i5-8400T has 2 more cores. Boost clocks reach 4.1 GHz on the Core i5-8279U versus 3.3 GHz on the Core i5-8400T — a 21.6% clock advantage for the Core i5-8279U (base: 2.4 GHz vs 1.7 GHz). The Core i5-8279U uses the Coffee Lake-U (2018−2019) architecture (14 nm), while the Core i5-8400T uses Coffee Lake (2017−2019) (14 nm). In PassMark, the Core i5-8279U scores 7,464 against the Core i5-8400T's 7,426 — a 0.5% lead for the Core i5-8279U. L3 cache: 6 MB (total) on the Core i5-8279U vs 9 MB (total) on the Core i5-8400T.

Feature	Core i5-8279U	Core i5-8400T
Cores / Threads	4 / 8	6 / 6+50%
Boost Clock	4.1 GHz+24%	3.3 GHz
Base Clock	2.4 GHz+41%	1.7 GHz
L3 Cache	6 MB (total)	9 MB (total)+50%
L2 Cache	256K (per core)	256K (per core)
Process	14 nm	14 nm
Architecture	Coffee Lake-U (2018−2019)	Coffee Lake (2017−2019)
PassMark	7,464	7,426
Cinebench R23 Multi	—	3,737
Geekbench 6 Single	—	1,092
Geekbench 6 Multi	—	3,816

🧠

Memory & Platform

The Core i5-8279U uses the FCBGA1528 socket (PCIe 3.0), while the Core i5-8400T uses LGA1151 (PCIe 3.0) — making them incompatible on the same motherboard.

Feature	Core i5-8279U	Core i5-8400T
Socket	FCBGA1528	LGA1151
PCIe Generation	PCIe 3.0	PCIe 3.0
Max RAM Speed	—	DDR4-2666
Max RAM Capacity	—	128 GB
RAM Channels	—	2
ECC Support	—	No
PCIe Lanes	—	16

🔧

Advanced Features

Virtualization: not specified (Core i5-8279U) / Yes (Core i5-8400T). The Core i5-8400T includes integrated graphics (UHD Graphics 630), while the Core i5-8279U requires a dedicated GPU.