DDR2 PC2-6400, DDR2 PC2-8500

Memory Type: DDR2 PC2-6400, DDR2 PC2-8500, DDR2 (non-ECC)
Maximum Memory: 16GB
Slots: 4

Although the memory can be installed one module at a time, the best performance comes from using matched pairs of modules.

How much memory your Windows OS will recognize depends on which version of Windows you are running. 32-bit versions of Windows will see (and utilize) only 3GB or 3.5GB. To utilize more memory, install a 64-bit version of your OS. More information about OS memory maximums can be found here.

Memory or DRAM is the "working" memory of the computer. It's used to store data for programs (sequences of instructions) on a temporary basis.

video - installing memory
SATA 2 - 3Gb/s

SATA Version -- SATA 2 - 3Gb/s
Storage Drives -- hard drives and solid state drives -- are the permanent memory for the programs and documents on your computer.
Data Transfer Rate is the rate at which data can be sent or received. This is determined by your motherboard. A drive with a higher transfer rate will only run at the rate of the motherboard's transfer rate.
Cache is a type of working memory that allows the drive to perform faster.
RPM is the rotations per minute of a hard drive which effects the speed of data transfer.
Solid State Drives are non-moving memory, so access speed is instant.
nVidia GeForce 6150SE chipset

Chipset is a set of integrated circuits that have a specific purpose in a computer system, a group of microchips used together to perform a single task.
PCI Express x16 Graphics

External Connector: 15-hole connector

Graphics Card A circuit board fitted to a computer containing the necessary video memory and other electronics to provide a bitmap display. Adaptors vary in the resolution (number of pixels) and number of colours they can display, and in the refresh rate they support. These parameters are also limited by the monitor to which the adaptor is connected.