The X299 (2017) PCH certainly still has the proper DMAC for LPC[1]. The first series you see lacking a DMAC core (or, at least one compatible with LPC/ISA DMA)

The X299 (2017) PCH certainly still has the proper DMAC for LPC[1]. The first series you see lacking a DMAC core (or, at least one compatible with LPC/ISA DMA) is the consumer 200 series of PCHs[2]. And it was fully gone by the 300 series[3]. It would seem that something in the switchover to the new streamed Intel HDA DMA architecture or going from DMI2.0->DMI3.0 left the functionality to the wayside. 1 - [PDF] https://cdrdv2-public.intel.com/335899/335899-005.pdf https://cdrdv2-public.intel.com/335899/335899-005.pdf 2 - [PDF] https://www.intel.com/content/dam/www/public/us/en/documents/datasheets/200-series-chipset-pch-datasheet-vol-1.pdf https://www.intel.com/content/dam/www/public/us/en/documents... 2 - [PDF] - https://www.intel.com/content/dam/www/public/us/en/documents/datasheets/300-series-chipset-pch-datasheet-vol-1.pdf https://www.intel.com/content/dam/www/public/us/en/documents...