I said "that they build" quite intentionally. Yes, the third-party PowerVR-based chipsets have little to no Linux support, a problem going back to the original GMA500 (Poulsbo) chipset, and that makes it difficult to make a blanket statement that all Intel graphics chipsets work with Linux. I'd still argue that Intel has the best Linux support among graphics card vendors; on top of that, Intel drives the majority of new innovations in the X and Linux graphics infrastructure code.