Introduction

The Intel Core i3-8300 is a new quad-core processor based on the "Coffee Lake" silicon, part of the company's second wave of 8th Generation Core processors, to expand choice on its 300-series chipset platform. This part sits bang in the middle of the Core i3-8100 quad-core and unlocked i3-8350K quad-core chip. AMD's successful Ryzen family of processors forced Intel to increase mainstream desktop processor core counts by 50-100 percent. The Core i5 and Core i7 series received 50 percent increases and are made up of 6-core parts, whereas the Core i3 series, which were dual-core until the 7th generation, received a 100 percent core-count increase and are now quad-core.

Within the Core i3 series, Intel nurtures two distinct sub-variants, the Core i3-x100 series and i3-x300 series. The two are usually differentiated by L3 cache amount. i3-x100 series SKUs from past generations featured 3 MB of L3 cache and were priced under the $140-mark, while the i3-x300 series SKUs packed 4 MB of L3 cache and were priced anywhere between $140-$180. With a 100 percent core-count increase comes a proportionate increase in L3 cache size. The Core i3-8100 which was part of Intel's first-wave of "Coffee Lake" chips, has 6 MB of it, while the i3-8350K has 8 MB. The new i3-8300 resembles the latter and comes with 8 MB of L3 cache.



Core i3 series desktop SKUs historically lacked both Turbo Boost, and the same is the case with the Core i3-8300. A minor 100 MHz in clock speed differentiates the i3-8100 from the i3-8300, besides L3 cache size. The i3-8300 is clocked at 3.70 GHz, 100 MHz higher than the i3-8100. The integrated graphics solution is almost the same between the two; you get UHD Graphics 630, armed with 24 execution units and 350 MHz nominal clocks, although the iGPU boost frequency is 50 MHz higher on the i3-8300, at 1.15 GHz.

The 100 MHz speed bump Intel coupled with 33 percent more L3 cache results in the Core i3-8300 being priced $20 (20%) higher than the i3-8100, at $139. Unlike the i3-8350K, it lacks an unlocked base-clock multiplier. In this review, we examine if the i3-8300 has enough muscle to warrant its increased price over the cheaper i3-8100 and similarly priced AMD Ryzen 3 1400.

A Closer Look

The Intel Core i3-8300 comes in a standard retail box, which includes a fan heatsink, case-badge, and some literature.


Intel's stock fan heatsink for the LGA115x sockets hasn't changed much within the past decade beyond evolving regulatory compliances (becoming lead-free, RoHS, etc.) It has the same top-flow cooler with a cylindrical heatsink with radially projecting, forked aluminium ridges, which is ventilated by a 70 mm fan. The Core i3-8300 has a TDP of 62 W, which is low enough to ensure that this relatively weak-looking cooler can run the processor fine all day.


The Core i3-8300 looks like every other LGA115x processor launched within the past decade. A point to note here is that unlike AMD, Intel is using glue and thermal paste as the interface material between the integrated heatspreader and die. Enthusiasts generally prefer soldered dies. Gamers don't care as long as their machines are quiet enough.


With this generation, the biggest point of confusion has been the package. The 8th generation Core desktop processors bear the "LGA 1151" package markings and look like they'll work on older 100-series and 200-series chipset motherboards. They'll even physically fit on them since nobody at Intel bothered to put the key notches elsewhere. The chips, however, will not work on older motherboards. The machine won't even POST. The box clearly states that you need a 300-series chipset motherboard to use the processor.

Architecture

The 8th generation Intel Core processors are based on the "Coffee Lake" micro-architecture. The CPU circuit design is essentially the same as with "Skylake," but the silicon is built on Intel's third iteration of the 14 nanometer silicon fab process, which the company refers to as 14 nm++. This node improves the ability for the chipmaker to dial up clock speeds at minimal power/thermal cost. The quad-core "Coffee Lake" silicon on which the Core i3-8300 is based physically features only four CPU cores and looks similar to the "Kaby Lake" silicon, albeit built on the new 14 nm++ node. The die area is roughly 127 mm².

The quad-core "Coffee Lake" silicon physically features four CPU cores with 256 KB of dedicated L2 cache per core and 8 MB of shared L3 cache. On the Core i3 "Coffee Lake" series, the L3 cache is reduced to 6 MB on the i3-81xx SKUs, but the i3-83xx SKUs, such as the i3-8300, get all of the available L3 cache. The integrated Gen 9.5 graphics core is physically carried over from the "Kaby Lake" die, but is bolstered by higher clocks and an enhanced driver, which lets Intel brand it as the "Intel UHD Graphics 600 series." Internal communication is handled by a "ring bus" and not the mesh-interconnect Intel deployed on its new Core X "Skylake-X" processors.



The system agent (the integrated Northbridge) also appears to be carried over from the "Kaby Lake" die with its dual-channel DDR4 memory interface. The Core i3 series SKUs feature a reference memory clock of DDR4-2400. The IMC supports XMP 2.0 profiles. The processor only puts out 16 PCI-Express gen 3.0 lanes meant for PEG (PCI-Express discrete graphics). It talks to the motherboard chipset over the DMI 3.0 chipset bus with 32 Gbps-per-direction bandwidth.



The "Coffee Lake" CPU core is of the same exact design as Skylake and Kaby Lake, which dates back to 2015. Compared to the Haswell/Broadwell core, it features an improved front-end with a 25% fatter 5 µOP pipeline, a 50% wider allocation queue depth, an improved branch-prediction unit, and a wider instruction window. The execution stage features a slightly bigger re-order buffer, a bigger integer register file, and an improved on-chip memory system. All of these contribute to a 5-10 percent IPC increase over "Haswell" to "Skylake" clock-for-clock.



Between "Skylake" and "Coffee Lake," Intel turned its R&D efforts towards refining the 14 nm process. It met with success on "Kaby Lake," and owing to its significantly higher clock speeds, "Kaby Lake" was able to provide higher performance than "Skylake." With "Coffee Lake," the nominal clock speeds look low, but Turbo Boost frequencies are higher than with "Kaby Lake," and refinements in the process allow the chip to sustain elevated boost-clock states better. As we mentioned throughout the introduction, the design focus of these chips is to increase core counts across the board in order to better compete with AMD Ryzen.

The Gen 9.5 integrated graphics core takes up nearly a third of the die area. Since it's of the same core configuration as the one on the "Kaby Lake" silicon, it still features 24 execution units in the GT2 trim. Higher clocks and some driver magic let Intel brand it "UHD Graphics." Don't expect to play PUBG at 4K on this, the "UHD" moniker only indicates that the IGP can handle 4K Ultra HD displays, features modern connectivity options such as DP 1.4 and HDMI 2.0, and can playback 4K video in new formats with 10-bit color and HDR10/Dolby Vision standards.

Intel 300-series Platform

Chipset options for the Core i3-8300 include the top-end Z370 Express which the platform debuted with, followed by the H370 Express, B360 Express, and entry-level H310 Express. The Z370 Express chipset, which succeeds the Z270 Express, appears to carry over the same platform feature set. The H370 has almost all features of the Z370, but one lesser M.2 slot, lack of CPU overclocking support, and lack of multi-GPU support. The B360 Express has fewer M.2 slots still. As we mentioned on the previous page, 8th generation Core processors won't work on 100-series/200-series chipset motherboards.