Somewhere, it should say how fast it is. This is the speed in nanoseconds. Consult your motherboard's manual to see what kinds of memory it can handle. In general, you don't want to get memory that is any slower than the memory currently on your computer. Make sure you don't exceed the amount of memory your motherboard can handle.
Different boards have different limits.
Also pay attention to chipset limitations, such as the TX's 64MB cacheable memory limit. Now I'll give you instructions to put it in. The actual installation is as easy as could be. The problems usually come from finding compatible memory, but even this is not a huge problem. Here is where you make sure the above guidelines are met.