RV770 features a 256-bit memory controller and is the first GPU to support GDDR5 memory, which runs at 900 MHz giving an effective transfer rate of 3.6 GHz and memory bandwidth of up to 115 GB/s. The RV770 also has 10 texture units, each of which can handle 4 addresses, 16 FP32 samples, and 4 FP32 filtering functions per clock cycle. The RV770 retains the R600's 4 Quad ROP cluster count, however, they are faster and now have dedicated hardware-based AA resolve in addition to the shader-based resolve of the R600 architecture. The RV770 extends the R600's unified shader architecture by increasing the stream processing unit count to 800 units (up from 320 units in the R600), which are grouped into 10 SIMD cores composed of 16 shader cores containing 4 FP MADD/DP ALUs and 1 MADD/transcendental ALU. All products implement TeraScale 1 microarchitecture.

This article is about all products under the brand 'Radeon HD 4000 Series'. Its direct competition was nVidia's GeForce 200 series, which launched in the same month. Other variants include enthusiast-oriented RV790, mainstream product RV730, RV740 and entry-level RV710. The foundation chip, codenamed RV770, was announced and demonstrated on Jas part of the FireStream 9250 and Cinema 2.0 initiative launch media event, with official release of the Radeon HD 4800 series on June 25, 2008. The Radeon R700 is the engineering codename for a graphics processing unit series developed by Advanced Micro Devices under the ATI brand name.

Hd 4000 driver