As we know, the Intel Coffee Lake desktop processors will not be backward compatible with previous-gen Intel 200 or 100-Series chipsets even though the new CPUs are based on the physically identical LGA1551 socket. The need for a new Z370 chipset is necessary as it was designed with optimized power delivery so that the Coffee Lake CPU to work properly at the rated performance. The move has however caused big disappointments among the PC enthusiasts, especially those who don’t want to spend more for a new motherboard.
Nowadays you can easily find a slew of computer sets with combination of the Core i3-8100 CPU and modified H110-chipset motherboard available in the Taobao marketplace. Recently, some forumers from Overclock.net and Win-Raid has published some guides on how to get the Coffee Lake CPUs to work with the Intel 100/200-Series chipsets.
In order to make Coffee Lake CPUs to work properly with the old motherboards, the UEFI BIOS has to be modified to include the Coffee Lake microcode. Other than that, you also need the correct Management Engine (ME) version to successfully boot the CPU, modification of iGPU vBIOS and GOP driver installation, as well as fixes for the PCIe x16 slot and CPU voltage readout.
It is also reported all MSI LGA1151 motherboards are able to work with 6-core CPUs such as the i5-8400 and even bootable with the flagship Core i7-8700K. However, it is not recommended to use the unlocked “K” series processors on the old motherboards, especially those with weak VRM design, as these CPU models are known to have a high power consumption that might result in system instability.