Amstrad GX4000

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The GX4000 was Amstrad's short-lived attempt to enter the games console market[1]. The console was released in Europe in 1990 and was an upgraded design based on the then still-popular CPC technology. The GX4000 shared hardware architecture with Amstrad's CPC Plus computer line, which were released concurrently, this allowed the system to be compatible with the majority of CPC Plus software.

The GX4000 was both Amstrad's first and only attempt at entering the console market. Although offering enhanced graphics capabilities, it failed to gain popularity in the market, and was quickly discontinued, selling 15,000 units in total.

A computer turned into a console[edit]

The GX4000 is a game console based on a 6128 Plus without a floppy controller or keyboard (although it is actually possible to modify one, add a floppy controller and a keyboard and use it as a Plus). It was delivered with two game paddles (as the ones delivered with the Plus models) and Burnin' Rubber on  cartridge (without BASIC). The GX4000 was Amstrad's attempt to gain some share in the home game console market, then dominated by the likes of Nintendo and Sega. Like others before it, and like others after it, it failed abysmally in its goal. Despite the fact that the hardware was decent (after all the CPC+ series were some of the very best 8-bit computers ever designed), it was a case of 'too little, too late'. Lack of CPC+ specific software, lack of marketing effort and bad timing meant that Amstrad's adventure in the home market was about to end.

Technical specifications[edit]

  • CPU: 8/16-bit Zilog Z80A at 4 MHz[1]
  • ASIC: Support for sprites, soft scrolling, programmable interrupts, DMA Sound[2]


  • Mode 0: 160x200 pixels with 16 colours
  • Mode 1: 320x200 pixels with 4 colours
  • Mode 2: 640x200 pixels with 2 colours


  • Depth: 12-bit RGB
  • Colours available: 4096
  • Maximum colours onscreen: 32 (16 for background, 15 for sprites, 1 for border)

Maximum onscreen colour counts can be increased in all Modes through the use of interrupts.

Sprites [2]

  • Number: 16 high resolution sprites per line
  • Sizes: 16x16 (each sprite can be magnified 2x or 4x in X and Y)
  • Colours: Each sprite can use up to 15 colours

Memory [2]

  • RAM: 64 kB
  • VRam: 16 kB : There is no real dedicated VRAM, RAM banks can be used as VRAM, the Z80 is then put on wait state while the video circuit reads the RAM bank. Also it is possible to get an overscan mode : the video circuit would read more than one RAM bank, the displayable zone is something like 24K.
  • ROM: 32 kB


  • 3-channel stereo; AY-3-8912 chip[1]. GX4000/Amstrad PLUS use the same AY as used on ORIC ATMOS, ZXspectrum128/+2/+3, MSX1, AmstradCPC or AtariST (YM clone), yet it may be clocked differently.
  • DMA


Audio output, 2x Digital controller connectors, Analog controller port (IBM standard [well, not exactly]), Lightgun connector (RJ11), Audio and RGB Video output (8-pin DIN), Power supply socket from external PSU, Power supply socket from monitor.

Cartridge Games[edit]