Gigaram 4GB (2x2GB) DDR2-800 ECC Fully Buffered DIMM for Apple Mac Pro 8-Core/Quad-Core 2.8Ghz (Apple# 1 x MB193G/A) Matched Pair of 2GB, PC2-6400, DDR2-800, 800Mhz, 5ns Cycle Time, ECC, Fully-Buffered, 256x72, 1.8V, 240pin FB-DIMMs Compatible with Apple Mac Pro 8-core/Quad-Core 2.8GHz, 3.0GHz or 3.2GHz Intel Xeon (MA970LL/A, A1186) (Early 2008). This kit contains two matched FB-DIMM modules, which are specifically designed and SPD configured for the Mac Pro These FB-DIMMs include full sized Apple spec heat sinks. They conform EXACTLY to the Apple original thermal spec. This module is compatible with the latest Apple Firmware