Upgrading your PC's memory One of the most popular ways to turn a slow machine into a fast machine is to add memory.
Most new computers have four slots for memory chips.
If you have 16 megabytes of memory, you probably have four, 4-megabyte memory chips, one in each slot. If you want to increase your memory to 40 megabytes, all you have to do is buy two 16-megabyte memory chips and put them in the first two memory slots. One rule is that you can't mix memory chips within the banks. Each set of two chips in each bank must be the same. The kind of memory chips you buy depends on your computer.