*The Spectrum 48k can't do double buffering in hardware, the Amstrad can. (To fix this problem on Spectrum they stored a bitmap in ram which they drew to, and then wrote changes to the screen). On the Amstrad you can use hardware double buffering, but then you need to sacrific twice as much video ram (e.g. 2 x 16K).
*The Spectrum has a fixed palette of 16 15 colours (8 colours with bright versions of each making 16 15 in total- LIGHT black is still black). Amstrad has a palette of 27 colours. In mode 0 you can choose 16 of these, in mode 1 you can choose 4 of these, in mode 2 you can choose 2 of these.
*The Spectrum's screen is "attribute" based. Each 8x8 cell can be assigned a background and foreground colour (and both colours must either be non-bright or bright). There is also the choice to flash the colours. This colouring results in "attribute/colour clash" on the Spectrum. The Amstrad's screen doesn't have this, and there is no restriction on how the colours can be placed.
*The Spectrum can display all 16 15 colours on the screen. The Amstrad can only do the same in mode 0, but this has fatter pixels. If the CPC's mode 1 resolution is chosen, this is not possible because only 4 colours can be chosen.
*The Spectrum has 1 interrupt per 50Hz frame, the Amstrad has 6 in fixed locations through the frame.
====Colours & Colour Clash====
The cell based colouring used on the Spectrum has it's its disadvantages. [[image:clash.png|right|thumb|Colour clashing in Knight Tyme. Observe the appearance of the character sprite as it merges with the background)]]
When moving a sprite over a background, or a sprite over another sprite, and if both have colours you have to decide which colours take priority.