AddOn AA32C6464-PC133 - 512MB SDRAM PC133 64X64 168-Pin Generic & Apple PowerMac G4

SDRAM are based on standard dynamic RAM chips but have sophisticated features that make them considerably faster. First SDRAM chips are fast enough to be synchronized with the CPU's clock which eliminates wait states.Second the SDRAM chip is divided into two cell blocks and data is interleaved between the two so that while a bit in one block is being accessed the bit in the other is being prepared for access. This allows SDRAM to burst the second and subsequent contiguous characters at a rate of 10ns compared to 60ns for the first character.