GDDR4 SDRAM is a type of graphics card memory that was intended to replace GDDR3. In 2005, Samsung developed the first 256-Mbit GDDR4 chip running at 2.5 Gbit/s. GDDR4 introduced technologies like Data Bus Inversion and Multi-Preamble to reduce power consumption and improve performance. While it achieved higher speeds and bandwidth than GDDR3, GDDR4 was quickly replaced by GDDR5 within a year as manufacturers like Qimonda moved directly to the newer standard.