The Q2X8G6400C4DHX is 8GB of DDR2 SDRAM DIMMs built using Corsair's latest high performance heat sink with Dual-Path Heat Xchange (DHX) technology. This part delivers outstanding performance in the latest generation of dual-channel DDR2-based motherboards. It has been tested extensively in multiple DDR2 motherboards to ensure compatibility and performance at its rated speed. This memory has been verified to operate at 800MHz at the low latencies of 4-4-4-12. Corsair's line of 8GB memory kits are designed for PCs featuring 64-bit operating systems. Please note: Installing 8GB onto PCs with 32-bit operating systems is not advised since 32-bit operating systems do not support 8GB of system memory.