Tested, and are in working condition:

-2 x i7-920 CPU

-4 x 2GB DDR3-1066 (PC3-8500) RAM Sticks

-6 x 2GB DDR3-1333 (PC3-10600) RAM Sticks

-1 x 4GB DDR3-1600 (PC3-12800S) Laptop RAM Sticks

-1 x 2GB DDR3-1600 (PC3-12800S) Laptop RAM Sticks 

Untest:

-1 x 4GB DDR3-1600 (PC3-12800) RAM Sticks

-1 x 2GB DDR3-1333 (PC3-10600) RAM Sticks

-1 x 1GB DDR3-1333 (PC3-10600) RAM Sticks

-2 x 2GB DDR3-1333 (PC3-10600) Laptop RAM Sticks