OCZ NVIDIA SLI Ready/Certified XTC Edition 240-pin DIMM DDR2 PC2-6400 800MHz 1GB SDRAM unbuffered system memory module; Heart pounding performance enhanced low Cas latency 4; CL 4-4-4-15 timings; Enhanced Performance Profiles (EPP) Ready; 2.1 volts; XTC (Xtreme Thermal Convection) Edition NVIDIA SLI logo heatspreader. 2.4V EVP (E)xtended (V)oltage (P)rotection. 100% hand tested. Lifetime warranty.