This document covers the basic hardware and software requirements to play Colossus. If you want to rebuild the game, please check the document Building Colossus.
Update 2012-12-03: Below values are very out of date. Currently required is a JRE 1.5, and since the JVM is started with a heap of 256 MB, you should have probably at least 512MB in your computer.Colossus should work with any Java Runtime Environment (JRE) or Java Development Kit (JDK / J2SDK) release 1.5 or newer. Building Colossus contains the links to the various JDK and JRE available.
On the hardware side, you'll need a color display (the higher the resolution the better, below 1024x768 is likely to look ugly) and enough RAM (128 MibiBytes should work, 256 MiB or more is better). A fast processor makes the game more comfortable, but as Colossus is turn-based, not real-time, it should work on about anything. For x86-family (i.e. Intel Pentium, AMD Athlon, etc.) processor, a speed of at least 200 megahertz should allow the game to run decently.
Finally, Colossus uses TCP sockets to communicate between client and server, even for local games . So if you have an old operating system that doesn't install networking by default, you may need to install it.
Colossus is free, so if in doubt, just try it.
The table below lists some tested configurations.
| Operating System | CPU | Memory | JRE / JDK version | Colossus version | Comments |
| MacOS X 10.1.3 | 667 Mhz PPC 7450 (G4) | 512 MiB | Apple-supplied 1.3.1 | 20020310 | Playable |
| Linux/PPC, kernel 2.4.18 | 192 Mhz PPC 604e | 128 MiB | Blackdown 1.3.1 PPC | 20020310 | Slow |
| Solaris 8 | 200 Mhz UltraSPARC I | 384 MiB | Sun 1.3.1 | 20020310 | Playable |
| Solaris 7 | 440 Mhz UltraSPARC II | 512 MiB | Sun 1.4.0 | 20020310 | Smooth |
| Solaris 2.6, CDE | 275 Mhz UltraSPARC II | 512 MiB | Sun 1.4.0 | 20020308 | Playable |
| Linux/x86, RedHat 7.2, KVM, kernel 2.4.17 | 633 MHz Pentium III | 512 MiB | Sun 1.4.0 | 20020308 | Fast |
| Linux/x86 RedHat 7.2, Sawfish, kernel 2.4.9 | Athlon XP 1800+ | 256 MiB | Sun 1.4.0 | 20020502 | Fast |
| Windows 98 | Athlon XP 1800+ | 256 MiB | Sun 1.4.0 | 20020502 | Fast |
| Windows 98 | 800 MHz Athlon Thunderbird | 256 MiB | Sun 1.4.0 | 20020502 | Fast |
Added comment January 2008: the values above are pretty outdated. I personally use currently Windows XP, 1 GB RAM, 2.6 GHz CPU.
But there are still users around using Win 98 and 128 MB; so it's doable. We are right now working on taking Java 1.5 into use, it might be a challenge to find a Java 1.5 for it, but Win98 SP2 is in the list of supported OSes for Java 1.5 - so it should be possible :)