One of the major problems with all RAM used in today's systems is that it can't keep up with processor speeds. For example, you may have a CPU that can run at 200 MHz but memory that runs at only 100 MHz. That causes bottlenecks in your system, and you won't get the performance gains you'd expect from upgrading to a faster CPU.
To solve this problem, vendors are working on new ways to speed up DRAM technology. Again, you need to know what your system supports; you won't get any additional performance gains from high-speed RAM if your system can't support that particular type of RAM. Following is an overview of some of the best RAM technologies out there--and what's coming up next.
- Fast Page Mode (FPM) DRAM was the type of RAM used in older Pentium systems. It's an improvement over older forms of DRAM because it accesses data in the same row faster. If data needed is in the same row as the previous data, the memory controller doesn't have to repeat the row location; it only needs to indicate the next column location. Typical FPM DRAM speeds are close to 30 MHz.
- Extended Data Output (EDO) DRAM reduces the amount of time it takes to read data from memory by transferring data on both the uptick and the downtick of the clock cycle rather than on just one-half of the cycle. It runs at about 50 MHz. This type of fast memory has been added to most Pentium and Pentium Pro systems sold in the past 12 months.
- Burst EDO (BEDO) DRAM is an innovation that allows a "burst," or series of data, to be transmitted from memory with a single request. It runs at about 66 MHz.
- Synchronous RAM (SRAM) synchronizes memory speed with the speed of the internal processor. With current technology, SRAM runs at 100 MHz. While SRAM is starting to appear in some systems, production is not yet high enough to meet demand. As chip production increases, however, SRAM is likely to become the dominant RAM technology over the next six months to a year.
- RDRAM or RAMBUS DRAM is a DRAM chip from Rambus Inc., a memory chip manufacturer. RDRAM will probably become the new standard in the next two years because it has the support of Intel Corp., the largest CPU manufacturer for PC systems. When this type of RAM becomes widely used, it should support high-speed transfer rates of 1.3GB, which will keep up with PC clock speeds. Currently, RDRAM is used only in some game machines and PC graphics applications.
If anything can improve your system's speed and life span, it's RAM. With these basics, you should know enough to upgrade your system.