In 64-bit mode, it's 4-Kbyte, 2-Mbyte and 1 Gbyte page sizes. 32-bit mode adds 4-Mbyte page sizes. Support for 1-Gbyte must be checked for via CPUID. The System Programming volume of the AMD64 Architecture Programmer's is a good place to get this info.
Figure 5-7 on Page 124 shows the 4-Mbyte page translation. Searching the document for "page size" should find numerous hits with relevant info.
http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/24593.pdf
-- Randy
Originally posted by: avk
LGS: AFAIK, several Linux distributives (mostly server-oriented like Red Hat and SuSe) support 1GB pages.