Intel Core i5-8400 vs Intel Core i7-1255U

Compare Intel 8th Generation Core i5 6 core CPU vs Intel 12th Generation Core i7 10 core processor, specs and benchmark score. Which is the better CPU for gaming?

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CPU Comparison

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Benchmark Score

Overall Score

A combined score of all workloads

3741 points

0.51% slightly better overall score

3722 points

Gaming Score

The raw gaming performance with a fast GPU

6024 points

8% slightly better gaming score

5577 points

Multitasking Score

Performance in workloads using up to 8 cores

3030 points

3201 points

5% slightly better multitasking score

Heavy Workload Score

Performance in workloads using up to 16 cores

2906 points

3089 points

6% slightly better heavy workload score

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Other Benchmarks

Blender score

Cycles Render (Samples per minute)

77.12 points

1% slightly higher Blender score

75.98 points

Specifications

Cores

Number of physical processing units

66% significantly more cores

Threads

Number of logical processing units

100% significantly more threads

Clock Speed

Base frequency at which the chip operates

2.8 GHz

64% significantly higher clock speed

1.7 GHz

Turbo Speed

Higher frequency used for heavy workloads

4 GHz

4.7 GHz

17% slightly higher turbo speed

TDP

Thermal Design Power: Measure of heat generated by the CPU

65 W

15 W

333% significantly lower TDP

PCIe Lanes

Number of physical connections between the CPU and expansion slots

25% slightly more pcie lanes

Memory Channels

Lanes for simultaneous memory access

Identical

Supported Memory

Maximum amount of RAM supported by this CPU

128 GiB

100% significantly more supported memory

64 GiB

L1 Cache

Smallest embedded memory, but the fastest

384 KiB

800 KiB

108% significantly more L1 cache

L2 Cache

Secondary embedded memory, slower than L1 cache

1.5 MiB

4 MiB

166% significantly more L2 cache

L3 Cache

General memory pool for all cores

9 MiB

12 MiB

33% slightly more L3 cache

Other details

Rank

Ranking in the hardwareDB database

456th of 1,089

459th of 1,089

Family

The product line

8th Generation Core i5

12th Generation Core i7

Release date

The official date of release of this chip

2017 November

2022 February

Memory Type

The type of memory used by this chip

DDR4-2666

DDR5-4800

Is Unlocked

Can this CPU can be overclocked

Supports ECC memory

Does this CPU support error correcting memory

Core i5-8400 vs Core i7-1255U benchmarks

Our benchmark analysis concludes that the Core i7-1255U performs better than the Core i5-8400. Furthermore, our gaming benchmark shows that it also outperforms the Core i5-8400 in all gaming tests too.

With info from our database, we find that the Core i7-1255U has significantly more cores with 10 cores whereas the Core i5-8400 has 6 cores. It also has more threads than the Core i5-8400. With our hardware info, we find that the Core i5-8400 has a significantly higher clock speed than the Core i7-1255U. Despite this, the Core i7-1255U has a slightly higher turbo speed. The Core i7-1255U outputs less heat than Core i5-8400 thanks to a significantly lower TDP. This measures the amount of heat they output and can be used to estimate power consumption. The cache sizes of these CPUs are different. Indeed, the Core i7-1255U has significantly more L2 cache than the Core i5-8400. The Core i7-1255U also has slightly more L3 cache.

The more cores a CPU has, the better the overall performance will be in parallel workloads such as multitasking. Many CPUs have more threads than cores, this means that each physical core is split into multiple logical cores, making them more efficient. For instance, the Core i5-8400 has the same number of threads as cores. This means the the CPU does not support hyperthreading.