Starting out with the basics, the Radeon HD 5800 series boasts a second-generation 40 nanometre GPU from AMD (with the Radeon HD 4770 their first 40 nanometre part) featuring a die size of 334 mm² against the 263 mm², 55 nanometre die used by RV770, a 1.27x size increase. This pales into comparison to the increase in transistor count however, with the Radeon HD 4870's 956 million transistors dwarfed by the 2.15 billion transistors employed by the Radeon HD 5800 series.