Intel GPU are namned by generation as GenX and they are built into the processor.

Intel GPU Architecture

Gen11 - 2019

A Slice contain Geometry, 8 Subslices, Slice Common and the L3 cache. Geometry is the 3D Geometry Fixed Function front-end. A Subslice contains eight Execution Units (EU), a 3d sampler unit, SLM and a Dataport. Each Execution Unit have two ALUs and thread state register files. Shared local Memory (SLM) memory that can be used by the EU's in the subslice without having to use the dataport to acces L3/Memory. The Texture Sampler is a read-only unit to sample textures. It supports decompression. The Dataport is used to access memory outside the subslice.

Slice common contains the Raster block, depth block and pixel dispatch and pixel backend. The raster block turns polygons into pixels. The depth block handles the z-buffer. Pixel Dispatch takes the pixels from the raster and send them to EU's. The pixel Backend (PBE) cache color values, write them out and blend them.

The L3 cache is 3 MB in size.

Gen9 - 2016

Gen8 - 2015

Gen7 - 2012

Gen6 - 2011

Gen5 - 2010

GPU moved from motherboard to the processor.

Gen4 - 2006

Gen3 - 2004

Gen2 - 2002

Gen1 - 1998

A trip through the Graphics Pipeline - 2011

The Architecture of 11th Generation Intel® Processor Graphics - 2019