The SAPPHIRE HD 4670 ULTIMATE Edition has been engineered by SAPPHIRE using heatpipe technology to bring a totally silent solution to this graphics family. With its 320 stream processors and carrying 512MB of GDDR3 memory the SAPPHIRE HD 4670 ULTIMATE is ideal for HTPC or general purpose computers that are required to run quietly but can also used for gaming. Clock speeds are 750MHz for the core and 873MHz (1.746GHz effective) for the memory.