The older computers also ran around 1 to 4 megahertz (MHz), whereas the Raspberry Pi runs at 700 MHz. And the Raspberry Pi is far from the average home PC. Today, boxes with 2 GB RAM and 2 GHz processor speed are common.
ASIO is a standardized way of describing the communication between audio software and a piece of audio hardware. It enables audio hardware manufacturers to write optimized drivers for their hardware that bypass the potentially high latency operating system mechanism for supporting audio hardware.
So, Steinberg (the Cubase people) made their own way to make drivers, called ASIO. This isn't part of Windows, and is sort of an agreement between pro audio sound card makers saying 'hey, if we all make our drivers like this, then applications can just support ASIO and everyone benefits'.