We’ve always wanted a 5360, and now we finally have one.

Editor’s note: The following images are from March 2026 and are being republished here as we work on uploading our backlog of images and project notes.

We like the IBM System/36 a lot. So much so that over the years, our club members have come to collect almost the entire System/36 hardware lineup. We collectively possess several 5362s (deskside), 5364s (desktop machines in the same form factor as the PC/AT, also called the Baby 36), 5363s (smaller deskside towers), and Advanced/36 machines (AS/400 RISC hardware running an emulated System/36). But one system that has eluded our grasp is the very first machine: the System/36 Model 5360. That recently changed with the acquisition of our Model 5360 Stage III machine.

The System/36 was the successor to the System/34, and was introduced to the market in 1983. The System/36 hardware and software architecture was largely the same as the System/34 – same MSP and CSP, same software (System Support Program) and programming language (RPG II) – just with the expected increase in processing speed and decrease in physical size. Notably, the System/36 also introduced the menu-driven navigation system that AS/400 users have grown to know over the years.

We would have been happy with any of the 5360 system units – Stage I, Stage II, or Stage III. We got lucky and obtained a Stage III machine with this rescue. What makes a Stage III so special? Compared to the Stage I, Stage II, and all other System/36 models on the market, the Stage III was – to borrow a phrase from Apple – wicked fast. It was the fastest production System/36 IBM ever offered until the Advanced/36 AS/400s started hitting the market.

Consequently, once the AS/400 hit the market and especially once the new RISC-based Advanced/36 machines came out, IBM began making aggressive trade deals to give customers fresh new machines and to ensure as many 5360 Stage III machines were taken off the market and destroyed. Our machine is one of the few 5360 Stage IIIs that escaped IBM’s scrapping efforts, likely because this machine was sold and supported by a third-party MSP instead of IBM themselves.

Currently, our 5360 Stage III does not run due to power supply problems. The Control Supply has a short in it somewhere and we keep blowing fuses on the +5v Base supply as soon as we apply power to the machine. There may also be other faults in the machine but we do not yet know what they are, if any. More details will be provided as we continue our restoration efforts on this machine.