A memory upgrade is typically the easiest and least expensive way to boost your computer's performance. While any time is good to add more memory, there are some scenarios in which adding a memory upgrade makes great sense and can dramatically improve your computer's performance:

You've upgraded your operating system (OS). You've installed memory-intensive software like photo-editing or a 3-D video game.
You work with large files or with three or more programmes at a time. You've added hardware, such as a new processor or a video card. You've purchased a new computer that came with too little system memory.

Dimm DDR2 1024MB 667Mhz Kingston Value Ram

Description : 1GB 667MHz DDR2 Non-ECC CL5 DIMM

Detailed Specifications : Standard 128M X 64 Non-ECC 667MHz 240-pin Unbuffered DIMM (SDRAM-DDR2, 1.8V, CL5, Double-Sided)

The components on this module include sixteen 64M x 8-bit (16M x 8-bit x 4 Bank) DDR2-667 SDRAM in FBGA packages. This 240-pin DIMM uses gold contact fingers and requires +1.8V. The electrical and mechanical specifications are as follows :

Features :
Clock Cycle Time (tCK) CL=5 : 3ns (min.) / 8ns (max.)

Row Cycle Time (tRC) : 54ns (min.)

Refresh to active/Refresh command time (tRFC) : 105ns (min.)

Row Active Time (tRAS) : 39ns (min.) / 70,000ns (max.)

Single Power Supply of : +1.8V (+/- .1V)

Power (IDD0) : 1.872 W (operating)

Operating Temperature : 0o C to 70 C

Storage Temperature : -55o C to +150 C

UL Rating : 94 V - 0