The possibility seems far less likely now. Gigabyte’s post reveals that Intel 9000-series support is being baked into BIOS updates for the company’s full motherboard product stack. Z370, H370, B360, and lowly H310 motherboards will all be updated for the next-gen CPUs. With MSI also announcing that its Z370 boards will receive 9th-gen BIOS updates, it seems likely that the motherboards you can buy today were designed from the ground up to support 8-core chips, though there’s still the chance that Intel limits 8-core chips alone to Z390.
What you need to know: Despite the abundant leaks, nothing’s certain until Intel officially announces 9th-gen CPUs itself. Also note that neither MSI or Gigabyte mention how many cores come in 9000-series chips, and Intel hasn’t formally announced plans for an 8-core mainstream chip. The leaked benchmarks and motherboard BIOS listings are strong evidence that a launch is coming sooner than later, but until we receive firm product details from Intel, this still falls into the rumor category.