Intel Core i5-8365U vs Intel Core i7-8665U

Intel Core i5-8365U

The Intel Core i5-8365U is a power efficient quad-core SoC for notebooks and Ultrabooks based on the Whiskey Lake generation and was announced in April 2019 as part of two vPro capable CPUs of the WHL-U series. Compared to the similar named Kaby Lake-R processors (e.g. Core i5-8250U), the Whiskey Lake CPUs are now produced in a further improved 14nm process (14nm++) and offer higher clock speeds. The architecture and features are the same. The i5-8365U offers e.g. high Turbo clock speeds of 4.1 GHz (versus 3.4 GHz of the i5-8250U) for a single core. The integrated GPU is still named Intel UHD Graphics 620 and the dual-channel memory controller still supports the same RAM speeds as Kaby-Lake-R (DDR4-2400 / LPDDR3-2133). Thermal Velocity Boost is not supported (only in the Core i7-8565U).

Compared to the predecessor, the Core i5-8265U, the i5-8365U offers a 200 MHz higher Turbo Boost. As the i5-8365U first appeared in a Thinkpad, the CPU most likely supports vPRO for additional hardware management features.

The Whiskey Lake SoCs are used with a new PCH produced in 14nm that supports USB 3.1 Gen 2 (10 Gbps) and CNVi WiFi/BT parts.

Architecture

Intel basically uses the same micro architecture compared to Skylake and Kaby Lake, so the per-MHz performance does not differ. That means Whiskey Lake is a Kaby Lake chip manufactured in the improved 14nm++ process.

Performance

The performance of the i5-8365U depends on the cooling solution of the laptop and the defined TDP limits for short and long term performance. We already saw big differences for Kaby Lake-R (e.g., i7-8550U benchmarks), especially for long term (sustained) performance. Therefore, it will be interesting to see how the additionalTurbo  clock speed can be made use of. Compared to the Core i5-8265U (see for benchmarks), the 200 MHz higher Turbo Boost should result in some gains in single core benchmarks.

Graphics

The integrated Intel UHD Graphics 620 (Intel Gen 9.5) is untouched from the 8th Gen Kaby Lake chips. With fast dual-channel memory it can reach the performance of a dedicated GeForce 920M.

Contrary to Skylake, Kaby Lake and Whiskey Lake now also supports H.265/HEVC Main 10 with a 10-bit color depth as well as Google's VP9 codec. The dual-core Kaby Lake processors announced in January should also support HDCP 2.2.

Power Consumption

The chip is manufactured in a further improved 14nm process with FinFET transistors (14nm++), the same as the 8th Gen Coffee Lake processors. Intel still specifies the TDP with 15 Watts, which is typical for ULV chips. Depending on the usage scenario, the TDP can vary between 7.5 (cTDP Down) and 25 Watts.

Intel Core i7-8665U

The Intel Core i7-8665U is a power efficient quad-core SoC for notebooks and Ultrabooks based on the Whiskey Lake generation that was announced in April 2019 as part of two vPro enabled WHL-U processors. Compared to the similar named Kaby Lake-R processors (e.g. Core i7-8550U), the Whiskey Lake CPUs are now produced in a further improved 14nm process (14nm++) and offer higher clock speeds. The architecture and features are the same. The i7-8665U offers e.g. high Turbo clock speeds of 4,8 GHz (versus 4 GHz of the i7-8550U) for a single core. The integrated GPU is still named Intel UHD Graphics 620 and the dual-channel memory controller still supports the same RAM speeds as Kaby-Lake-R (DDR4-2400 / LPDDR3-2133). Compared to the slower Core i5-8265U and i3-8145U, the i7 should support Thermal Velocity Boost (like the Core i7-8565U, the predecessor).

The Whiskey Lake SoCs are used with a new PCH produced in 14nm that supports USB 3.1 Gen 2 (10 Gbps) and CNVi WiFi/BT parts.

Architecture

Intel basically uses the same micro architecture compared to Skylake and Kaby Lake, so the per-MHz performance does not differ. That means Whiskey Lake is a Kaby Lake chip manufactured in the improved 14nm++ process.

Performance

The performance of the i7-8665U depends on the cooling solution of the laptop and the defined TDP limits for short and long term performance. We already saw big differences for Kaby Lake-R (e.g., i7-8550U benchmarks), especially for long term (sustained) performance. Therefore, it will be interesting to see how the additionalTurbo  clock speed can be made use of. Due to the 200 MHz higher Turbo Boost, the 8665U should outperform the i7-8565U (see for benchmarks).

Graphics

The integrated Intel UHD Graphics 620 (Intel Gen 9.5) is untouched from the 8th Gen Kaby Lake chips. With fast dual-channel memory it can reach the performance of a dedicated GeForce 920M.

Contrary to Skylake, Kaby Lake and Whiskey Lake now also supports H.265/HEVC Main 10 with a 10-bit color depth as well as Google's VP9 codec. The dual-core Kaby Lake processors announced in January should also support HDCP 2.2.

Power Consumption

The chip is manufactured in a further improved 14nm process with FinFET transistors (14nm++), the same as the 8th Gen Coffee Lake processors. Intel still specifies the TDP with 15 Watts, which is typical for ULV chips. Depending on the usage scenario, the TDP can vary between 7.5 (cTDP Down) and 25 Watts.