USB Alternative
PS/2
PS/2 is a legacy computer input interface used mainly for keyboards and mice, with dedicated Mini-DIN connections that USB largely replaced on modern PCs.
Overview · Comparison to USB · Use cases · Articles
Related: Apple Desktop Bus · Bluetooth · Serial Ports
PS/2 overview
Review PS/2 as a legacy keyboard and mouse interface, including its Mini-DIN connector, dedicated input-device role, hot-plug limitations, and current specialized use.
| Primary purpose | Keyboard and pointing-device input |
|---|---|
| Common connector | 6-pin Mini-DIN |
| Typical devices | Keyboards and mice |
| General peripheral data | No; PS/2 is dedicated to keyboard and mouse input |
| Hot plugging | Legacy systems were not designed around USB-style hot plugging |
| Typical PC implementation | Separate keyboard and mouse ports or a shared dual-purpose PS/2 port |
| Current status | Legacy and specialized |
Sources: Intel Workstation Board S975XBX2 technical specification.
PS/2 comparison to USB
Compare PS/2 with USB for keyboard and mouse support, hot plugging, peripheral range, hubs, legacy firmware support, and modern system compatibility.
| Factor | PS/2 | USB |
|---|---|---|
| Primary role | Dedicated keyboard and mouse connection | General-purpose peripheral bus for input devices and many other device classes |
| Connector | 6-pin Mini-DIN | USB-A, USB-C, and other USB connector forms |
| Hot plugging | Not a core design expectation on legacy PS/2 hardware | Designed for plug-and-play peripheral connection |
| Peripheral range | Primarily keyboards and mice | Keyboards, mice, storage, audio, cameras, printers, hubs, and many more devices |
| Legacy support | Native on older PC hardware | Firmware can emulate PS/2-style keyboard and mouse behavior for legacy software |
| Best fit | Existing systems or specialized hardware that still provides PS/2 | Nearly all modern keyboards, mice, and general peripherals |
Sources: Intel legacy USB and PS/2 support documentation and USB-IF USB4.
PS/2 use cases
See where PS/2 still makes sense for older desktops, firmware-level input, specialized systems, and existing keyboards or mice, and where USB is the better modern choice.
| Use case | Why PS/2 fits | Better modern option |
|---|---|---|
| Older desktop PC | The motherboard may provide native PS/2 keyboard and mouse ports | Keep PS/2 when convenient; USB works for most modern peripherals |
| Legacy firmware or software | Native PS/2 can avoid reliance on USB support in older environments | USB with firmware legacy-input support on newer systems |
| Existing PS/2 keyboard | Direct connection avoids replacing working legacy hardware | USB keyboard when moving to systems without PS/2 |
| Specialized industrial system | Some long-lived equipment may retain PS/2 for dedicated input | Use the interface required by the maintained system |
| New computer setup | PS/2 offers little general advantage for most users | USB is the practical default |
Sources: Intel Workstation Board S975XBX2 technical specification.
PS/2 articles
Explore guides comparing PS/2 and USB keyboards and mice, adapter compatibility, legacy hardware, and common peripheral connection questions.
