AMD's Phenom II X4 975 Black Edition is a quad-core, 3.6GHz socket AM3 chip with 6MB of L3 cache and 512KB of L2 cache per core. It's being released in tandem with the AMD Phenom II X4 840 CPU. Both processors are ideally suited to socket AM3 motherboards built around the recent AMD 890FX or 890GX chipsets. The Phenom II X4 975 BE is backwards compatible with socket AM2+ motherboards and forwards compatible with the as yet unreleased socket AM3+ platform.