OCZ Reaper HPC 4GB (2 x 2GB) PC2-6400 DDR2 SDRAM Desktop Memory for $29.99 shipped after this $20 rebate. Here is a screenshot for your reference. This memory operates at 2.1V at a speed of 800MHz. It usually goes for over $50.
OCZ2RPR10664GK
OCZ Reaper HPC 4GB (2 x 2GB) PC2-8500 DDR2 Memory Kit for $29.89 Shipped
OCZ Reaper HPC 4GB (2 x 2GB) PC2-8500 DDR2 SDRAM Memory Kit for $29.89 shipped after this $20 rebate. Here is a screenshot for your reference. This memory operates at 2.1V at a speed of 1066MHz. It usually goes for over $45.