AMD on Thursday retook the top spot for single-card graphics speed through the Radeon HD 7970. The video card is the first anywhere to use a 28 nanometer chipmaking process and uses this to pack 2,048 cores, or a third more than the Radeon HD 6970 it's replacing. Performance comes also through a newly widened 384-bit memory bus, PCI Express 3.0, and a full 3GB of GDDR5 memory, again a record for a single-chip card.
