CPU Comparison
Intel Core i5-8400T vs Intel Core i5-9400T
A side-by-side comparison of specs, performance and value. The Intel Core i5-8400T is a low-power desktop processor belonging to the 8th generation Coffee Lake family. Released in April 2018, it is built on the 14nm process and features 6 cores and 6 threads. Unlike the standard i5-8400, the 'T' suffix denotes a reduced 35W TDP, making it ideal for small form factor (SFF) PCs and home theater setups. The base clock is set at 1.7 GHz, with a maximum turbo boost of 3.3 GHz. It includes 9 MB of Intel Smart Cache and supports dual-channel DDR4 memory up to 2666 MT/s. The integrated Intel UHD Graphics 630 handles basic display tasks. With 16 PCIe 3.0 lanes, it provides adequate expansion options. The i5-8400T is compatible with LGA 1151 sockets, though it requires 300-series chipsets for official support, offering a balance of efficiency and multi-core capability.
The Bottom Line
Overview & Launch
Specifications Compared
Performance Compared
Productivity
6 cores handle office tasks easily, though single-core is slower.
Handles office applications, large spreadsheets, and multitasking without issues.
Gaming
Can handle light gaming, but low clocks limit high-refresh gaming.
Capable of light eSports gaming using integrated graphics, but not suited for AAA titles.
Virtualization
Good for 1-2 VMs, but lacks hyper-threading.
Can run basic VMs, but lacks Hyper-Threading for heavy parallel workloads.
Efficiency
Outstanding efficiency with a 35W TDP.
Outstanding power-to-performance ratio for low-power segments.
Specialized Performance
AI / ML
- No dedicated AI hardware.
- Low clocks make inference slow.
- No dedicated AI hardware
- Low core clocks limit CPU-based inference
Content Creation
Gaming
- Low base clock can cause stuttering in CPU-bound games.
- UHD 630 is only good for very light titles.
- Best paired with a low-end discrete GPU if gaming.
- UHD 630 handles older or lightweight games well
- Pairs best with discrete GPUs for 1080p gaming
- Not ideal for high-refresh-rate AAA gaming
Industry Impact
Best CPU by Use Case
Target Audience
Strengths & Weaknesses
Pros
- Extremely low 35W TDP
- 6 cores for parallel tasks
- Runs very cool
- Good for small form factor builds
Cons
- Low base and boost clocks
- Locked multiplier
- No Hyper-Threading
- End-of-life platform
Pros
- Extremely low 35W TDP
- 6 physical cores for multitasking
- Integrated UHD Graphics 630
- Runs exceptionally cool
- Quiet operation potential
Cons
- Low base clock of 1.8 GHz
- No Hyper-Threading
- Locked multiplier
- End-of-life platform
- Limited upgrade path
Competitors & Alternatives
Intel Core i5-8400T
- AMD Ryzen 5 2400GERival
Low Power Desktop
- Compare head-to-headIntel Core i5-8400Rival
Mainstream Desktop
- AMD Ryzen 5 2600ERival
Low Power Desktop
- Compare head-to-headIntel Core i5-7400TRival
Previous Gen Low Power
- AMD Ryzen 3 2200GERival
Budget Low Power
Slightly faster clocks, same TDP.
Compare head-to-head- AMD Ryzen 5 3400GEAlt
Better integrated graphics.
Much faster modern architecture.
Compare head-to-head- AMD Ryzen 5 5600GEAlt
Better efficiency and performance.
Slightly higher clocks if buying used.
Compare head-to-head
Intel Core i5-9400T
- AMD Ryzen 5 2600ERival
Low Power Desktop
- AMD Ryzen 5 3400GERival
Low Power Desktop
- Compare head-to-headIntel Core i5-8500TRival
Low Power Desktop
- Compare head-to-headIntel Core i7-8700TRival
Low Power Desktop
- AMD Ryzen 3 3200GERival
Low Power Desktop
Better raw performance if power constraints are not a strict issue.
Compare head-to-headSlightly higher clocks within the same 35W envelope.
Compare head-to-head- Intel Core i3-9100Alt
Cheaper alternative for basic office needs.
- AMD Ryzen 5 3400GAlt
Significantly better integrated graphics performance.
- Intel Core i5-10400TAlt
Newer generation with Hyper-Threading support.
Our Verdict on Each
A highly efficient 6-core processor perfect for compact builds, though its low clock speeds limit performance compared to the standard 8400.
Best for: Building a quiet home server or retro gaming rig on a budget.
Read the full reviewAn efficient 6-core chip that trades raw clock speed for a strict 35W thermal envelope, making it perfect for compact systems but less ideal for heavy workloads.
Best for: Building or upgrading a low-power, small form factor system where a 35W TDP is strictly required.
Read the full reviewFrequently Asked Questions
Which is faster for gaming, Intel Core i5-8400T or Intel Core i5-9400T?
For gaming, the Intel Core i5-9400T leads with a gaming performance score of 55/100 among Intel Core i5-8400T and Intel Core i5-9400T.
Do Intel Core i5-8400T and Intel Core i5-9400T use the same socket?
No. They use different sockets (Intel Core i5-8400T: LGA 1151, Intel Core i5-9400T: Intel Socket 1151), so each needs a compatible motherboard.
Which is faster in multi-core benchmarks?
The Intel Core i5-8400T posts the highest multi-core benchmark score. Multi-core results: Intel Core i5-8400T (8,500). Benchmark figures are approximate and workload-dependent.