Why chip density, compatibility, and pricing are related
When it comes to Crucial memory, we strive to keep our prices as low as possible. But there are times when you might find our competitors selling what appears to be the exact same memory ... for a lower price. At first glance, it might look like our competitors' product is the exact same as ours and would make a better buy, think twice. There's a lot more going on behind the scenes than initially meets the eye. Enter the complex relationship between chip density, compatibility, and pricing.
Chip density and compatibility
When computer manufacturers design and build new systems, they try to enable support for all DRAM chip densities that are available at the time. Many years ago when the first PC100 systems were released, the only DRAM densities available were 16Mb chips and 64Mb chips. However, 128Mb chips were in the design phase, so computer manufacturers enabled 128Mb density support.
Since then, chip density has increased dramatically, and with the launch of DDR4 memory technology, chip density is expected to top 8Gb. In general, density increases serve two purposes: they allow more performance to be packed into a single module, and they allow memory manufacturers to reduce the cost-per-bit when they adjust production to chips with greater densities. As manufacturers increase the amount of density per chip and migrate to newer processes, the production cost per gigabit decreases.
Compatibility and pricing
While the cost of production per gigabit has tended to decrease, the market price of memory chips remains largely governed by supply and demand. As demand increases for higher-density chips, the demand for older, lower-density chips usually declines. Memory manufacturers typically adjust production accordingly.
If the supply of lower density chips decreases faster than demand, the price per bit on these chips will remain high compared to the price of newer, higher-density chips. That's when pricing discrepancies tend to arrive: when older systems are unable to support newer, higher-density and lower priced chips. Since a computer's chipset can only support the type of memory technology that it was designed for, many systems can only support more expensive lower-density modules.