What is Simultaneous Multithreading?

Simultaneous multithreading, abbreviated as SMT, is the process of a CPU splitting each of its physical cores into virtual cores, which are known as threads. This is done in order to increase performance and allow each core to run two instruction streams at once.

Intel branded this process as hyper-threading, but hyper-threading is the same thing as simultaneous multithreading. For example, AMD CPUs with four cores use simultaneous multithreading to provide eight threads, and most Intel CPUs with two cores use hyper-threading to provide four threads.

SMT increases CPU performance by improving the processor’s efficiency, thereby allowing you to run multiple demanding apps at the same time or use heavily-threaded apps without the PC lagging.

SMT stands for Simultaneous Multithreading and was first properly adopted for modern CPU use back in 2002 by Intel, with the Northwood-based Intel Pentium 4 under the name Hyper-threading. AMD however was a little late to the party, developing its first processor with SMT support in 2017 with the Ryzen 7 1700. AMD had multithreading support earlier but this came in the form of CMT (cluster-based multithreading) on its Bulldozer series CPUs.

SMT is AMD’s brand of multithreading, Hyperthreading is Intel’s. They are effectively the same technology, for the most part, just different names.

The easiest way to see if it’s enabled, see on our System Monitor II gadget.