High density electronic circuits are often called 'chips' or 'microchips' because they're laid out on a small square of silicon or another thin, flat substrate. That's what's embedded inside the plastic/ceramic squares inside your computer. 'Chipset' then, generally refers to a collection of microchips designed together to handle some task. In the context of graphic driver development, there are generally two senses used. Specifically, 'chipset' can refer to the particular acceleration engine used in your graphics card (such as 'ATI Rage Pro', 'Voodoo 3', or 'Matrox G400'.) This term is also (more generally) used to refer to the larger chips on your motherboard which interface between the main processor, memory, and the various peripherals. If you're talking about, e.g., the agpgart kernel driver for dma support, this is the chipset people will be asking about (such as '440BX' or 'VIA MVP3'.) These days, the 'chipset' may well be integrated into a single package, but the historical usage persists.