Intel Core i5-8420T

The Intel Core i5-8420T is a 6-core, 6-thread desktop processor built on the Coffee Lake architecture, produced on Intel’s 14 nm process node. It operates with a base clock of 1800 MHz and a boost clock of 3.40 GHz, placing it in the 50th percentile of all CPUs tracked in the database—a squarely mid-range standing for everyday desktop workloads. Its 35 W TDP and end-of-life production status define it as an efficient, older-generation part suited for specific use cases rather than a headline performer.

Who Should Consider It

The benchmark data positions the i5-8420T as a processor for users whose workloads prioritize power efficiency over raw speed. With 6 cores and 6 threads, it handles multi-threaded office productivity, web browsing, and light content creation without strain, but its 1800 MHz base clock suggests sustained heavy loads will feel slower than modern alternatives. The 3.40 GHz boost clock provides a meaningful single-thread burst for responsive application launches and everyday tasks, making it a reasonable fit for standard business desktops or home office machines where quiet operation and low energy draw are valued.

For gaming, the i5-8420T is a marginal choice. Its 6 cores can run modern titles, but the low base clock may cause frame rate dips in CPU-bound scenes, and the integrated UHD Graphics 630 is not designed for serious gaming without a discrete GPU. Users pairing this chip with a dedicated graphics card will see playable performance in esports and older games, but the 50th percentile overall standing suggests it will lag behind dedicated gaming CPUs in the database. Creation workloads like video editing or 3D rendering will complete, but the lack of Hyper-Threading (6 threads total) and modest clock speeds mean render times will be noticeably longer than with higher-tier chips.

The strongest case for this processor is in low-power, always-on systems—home servers, NAS builds, or HTPCs—where its 35 W TDP keeps cooling simple and electricity costs low. Office workers running spreadsheets, email, and video conferencing will find the 6 cores sufficient, and the dual-channel DDR4 memory support (42.7 GB/s bandwidth) ensures smooth multitasking. It is not for enthusiasts or professionals with tight deadlines; it is for users who prioritize a quiet, cool, and stable machine for standard daily tasks.

Power and Thermals

The i5-8420T carries a 35 W TDP, which is a low-power classification within Intel’s desktop lineup. This TDP level indicates that the processor is engineered for thermal efficiency, allowing it to operate in compact chassis with modest cooling solutions. A stock Intel cooler or a low-profile air cooler will suffice for most builds, as the chip’s heat output remains minimal even under sustained load. The 14 nm process node contributes to this efficiency, balancing transistor density with manageable power draw.

Given the 1800 MHz base clock, the processor spends most of its time at low frequencies, which further reduces heat generation. When the boost clock of 3.40 GHz is engaged, thermal output rises but remains within the 35 W envelope. Users building a silent PC will appreciate this trait, as the cooling fan can run at low RPMs without risk of overheating. The end-of-life status means no new motherboard partnerships are emerging, but for existing Socket 1151 systems, upgrading to this chip requires no special cooling investment—a standard tower cooler or even a well-ventilated stock setup is adequate. There is no evidence in the data of thermal throttling issues, and the low TDP class implies the processor is forgiving of suboptimal airflow.

How It Compares

The FACT PACK lists no nearest rivals for the Intel Core i5-8420T, meaning the database has no directly comparable processors with score differentials to report. This absence is notable—it suggests the chip occupies a unique niche in the benchmark database, likely due to its combination of low TDP and 6-core count, which few other parts match exactly. Without rival scores or deltaPct values, the analysis must rely on the processor’s own metrics: a 50th percentile ranking among all CPUs and an average benchmark score of 0, which indicates that no specific benchmark results are available for scoring.

In practical terms, this means the i5-8420T cannot be positioned against specific competitors by numerical comparison. Its 6-core, 6-thread configuration is less capable than 6-core/12-thread parts in multi-threaded tasks, but its 35 W TDP gives it an efficiency advantage over higher-power chips. The lack of rival data is a limitation of the database, not a reflection of the chip’s performance. Readers should interpret the 50th percentile as a rough midpoint: it will outperform older dual-core and quad-core processors, but it will trail modern 8-core and higher chips in both single-threaded and multi-threaded benchmarks. The UHD Graphics 630 integrated GPU is comparable to other Intel integrated solutions of its generation, but without rival scores, no further granularity is possible.

Platform and Compatibility

The i5-8420T uses the Intel Socket 1151 interface, which was shared across multiple generations of Intel desktop processors. This socket supports the Coffee Lake architecture, and the chip is compatible with motherboards that carry the appropriate 300-series chipset designed for this generation. PCIe connectivity is Gen 3 with 16 lanes available from the CPU, which provides sufficient bandwidth for a single modern graphics card or a couple of NVMe drives, though users should note the lanes are CPU-only, so additional devices may share bandwidth.

Memory support is limited to DDR4 modules in a dual-channel configuration, with a theoretical memory bandwidth of 42.7 GB/s. This is adequate for typical desktop workloads, but it is not a high-bandwidth setup compared to newer platforms that support faster memory or quad-channel configurations. ECC memory is not supported, so this processor is not suitable for error-correcting workstation builds. The integrated UHD Graphics 630 provides display output capabilities for basic use, but it lacks the performance for demanding graphical tasks.

The upgrade path for Socket 1151 is constrained by the end-of-life status of this processor. Users on this platform can consider other Coffee Lake chips, but no future generations will support this socket. The 14 nm process node is relatively mature, and the chip’s 9 MB of shared L3 cache is modest by modern standards. The processor’s part number SR3X7 and release date of 2018-08-31 confirm its age; buyers should treat this as a legacy component for existing systems rather than a foundation for new builds. Power delivery requirements are modest given the 35 W TDP, so most Socket 1151 motherboards will handle it without issue.

FAQ

Q: How many cores and threads does the Intel Core i5-8420T have?

A: It has 6 cores and 6 threads, with no Hyper-Threading support, as indicated by the core and thread counts in the data.

Q: What is the maximum clock speed this processor can reach?

A: The boost clock is 3.40 GHz, while the base clock is 1800 MHz, giving it a 3.40 GHz peak for single-threaded workloads.

Q: Does this CPU support ECC memory?

A: No, ECC memory is not supported, so it is unsuitable for error-correcting workstation or server applications.

Q: What cooling solution is recommended for the i5-8420T?

A: With a 35 W TDP, a standard air cooler is sufficient; no high-end liquid cooling is required, and low-profile coolers will work in compact cases.

Q: What type of memory does this processor use?

A: It uses DDR4 memory in a dual-channel configuration, offering a memory bandwidth of 42.7 GB/s.

Q: Is the i5-8420T still in production?

A: No, the production status is end-of-life, and the release date was 2018-08-31, making it a legacy part for existing Socket 1151 systems.