Intel Core i7-8700 vs Intel Core i7-6820HQ vs Intel Core i5-8400

Intel Core i7-8700

The Intel Core i7-8700 is a high-end desktop processor with six cores based on the Coffee Lake architecture and was announced in September 2017. The processor clocks at between 3.2 and 4.6 GHz and can execute up to twelve threads simultaneously thanks to Hyper-Threading. According to Intel, the CPU is manufactured in an improved 14nm (14nm++) process. Compared to the slightly higher clocked Core i7-8700K, the i7-8700 offers a lower TDP and no unlocked multiplier (no easy overclocking).

Performance

Due to the two additional cores, performance has increased by almost 50% compared to the previous quad-core Kaby Lake models. Single-core performance has not improved much. As a high-end model, the i7-8700 is suitable for the most demanding applications and games.

Graphics

The integrated Intel UHD Graphics 630 iGPU is supposed to offer higher performance as its clock rate has been increased by 50 MHz. The build is identical to that of the Intel HD Graphics 630. We do expect a performance improvement, but as a low-end solution it will probably only display current games smoothly at reduced details - if at all.

Power Consumption

Intel specifies the TDP with 65 watts. Therefore, well-dimensioned cooling systems should easily manage to deal with the created heat. We expect increased efficiency due to the higher performance.

Intel Core i7-6820HQ

The Intel Core i7-6820HQ is a quad-core processor based on the Skylake architecture, that has been launched in September 2015. In addition to four CPU cores with Hyper-Threading clocked at 2.7 - 3.6 GHz (4 cores: max. 3.2 GHz, 2 cores: max. 3.4 GHz), the chip also integrates an HD Graphics 530 GPU and a dual-channel DDR4-2133/DDR3L-1600 memory controller. The CPU is manufactured using a 14 nm process with FinFET transistors.

Compared to the very similar Core i7-6820HK, the Core i7-6820HQ supports additional administration and security features like Intel vPro and TXT, but lacks the unlocked multiplier for OC.

Architecture

Skylake replaces both Haswell and Broadwell and brings the same microarchitecture in every TDP class from 4.5 to 45 W. The extensive improvements of the Skylake design include increased out-of-order buffers, optimized prefetching and branch prediction as well as additional performance gains through Hyper-Threading. Overall, however, performance per clock has been increased by only 5 to 10 percent (compared to Haswell) respectively under 5 percent (compard to Broadwell), which is quite modest for a new architecture ("Tock").

Performance

Thanks to the improved architecture, the Core i7-6820HQ performs roughly on par with the former Core i7-4900MQ (Haswell) or the Core i7-5700HQ (Broadwell). Under long-lasting full load, the Skylake chip will take the lead over most of its Haswell-based predecessors, as the advanced 14 nm process leads to a higher energy efficiency and reduces throttling.

Even the most demanding applications and excessive multitasking are handled easily.

Graphics

The integrated graphics unit called HD Graphics 530 represents the "GT2" version of the Skylake GPU (Intel Gen. 9). The 24 Execution Units, also called EUs, are clocked at 350 - 1050 MHz and offer a performance about 20 percent above the old HD Graphics 4600. Games of 2015 can thus be played smoothly in low or medium settings. For more information about performance and features, check our page for the HD Graphics 530.

Power Consumption

Specified at a TDP of 45 W (including CPU, GPU and memory controller), the CPU is best suited for bigger notebooks 15-inches in size and above. Optionally, the TDP can be lowered to 35 watts (cTDP down), reducing both heat dissipation and performance.

Intel Core i5-8400

The Intel Core i5-8400 is a mid-range 6-core CPU. The processor belongs to the Coffee Lake generation and was presented in September 2017. It does not support Hyper-Threading, which means it can run six threads simultaneously. The base clock rate is 2.8 GHz and the CPU can speed up to 4.0 GHz under high load. Despite belonging to the new generation of CPUs, the Core i5-8400 is manufactured in an improved 14nm process.

Performance

The processor offers a strong performance increase compared to the Core i5-7400 due to its two additional cores. Single-core performance has not improved significantly compared to its Kaby Lake predecessor. As a mid-range model, the Core i5-8400 should be suitable for demanding games and programs.

Graphics

The integrated Intel UHD Graphics 630 iGPU is supposed to offer higher performance as its clock rate has been increased by 50 MHz. The build is identical to that of the Intel HD Graphics 630. We do expect a performance improvement, but as a low-end solution it will probably only display current games smoothly at reduced details - if at all.

Power Consumption

Intel specifies the TDP with 65 watts. Therefore, well-dimensioned cooling systems should easily manage to deal with the created heat. We expect increased efficiency due to the higher performance.