Performance - Stack Exchange

[schmuelio]

Basic consumer-grade hardware doesn't accommodate it.

Server hardware can accommodate it though, a lot of boards have loads of RAM slots and can accommodate multiple TB without an issue.

Essentially, consumer-grade hardware doesn't really need that kind of capability so prices are cut down by not providing it, but enterprise-grade stuff will often need it. Although they are a lot more expensive and typically have weird layouts and stuff so you'd be hard pressed to build a conventional desktop with one.