Can't open screen (Chip memory)
Commodore Amiga
Severity: ModerateWhat Does This Error Mean?
This error means the Amiga does not have enough Chip RAM to open a new screen. Chip RAM is special memory used for graphics, sound, and the display — it is separate from Fast RAM. Close other screens, reduce screen colours or resolution, or add more Chip RAM.
Affected Models
- Commodore Amiga 500
- Commodore Amiga 500+
- Commodore Amiga 600
- Commodore Amiga 1200
- Commodore Amiga 2000
- Commodore Amiga 3000
- Commodore Amiga 4000
- WinUAE emulator
Common Causes
- Too many screens or windows open, consuming all Chip RAM
- Program requesting a high-resolution or high-colour screen that needs more Chip than available
- Only 512KB Chip RAM on an unexpanded Amiga 500
- Chip RAM fragmented — enough total but not in one contiguous block
- Large images or animations loaded into Chip RAM
How to Fix It
-
Close other programs and screens to free Chip RAM.
Type AVAIL in a Shell to see how much Chip RAM is free. Close Workbench screens and programs you are not using.
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Reduce the screen resolution or number of colours.
Higher resolutions and more colours use more Chip RAM. A 640x256 4-colour screen uses far less Chip RAM than a 640x512 256-colour screen.
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Upgrade Chip RAM to 1MB or 2MB.
The Amiga 500 originally has 512KB Chip RAM. A trapdoor expansion or internal modification can add 512KB more. The A1200 has 2MB Chip RAM as standard.
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On WinUAE: set Chip RAM to 2MB in the hardware settings.
Go to Hardware > RAM and set Chip RAM to 2 MB. This matches the maximum Chip RAM the Amiga chipset supports (ECS/AGA).
Frequently Asked Questions
What is the difference between Chip RAM and Fast RAM?
Chip RAM can be accessed by both the CPU and the custom chips (Agnus, Denise, Paula). Fast RAM can only be accessed by the CPU — it is faster but cannot be used for graphics or sound. The Amiga needs Chip RAM for all display, sprites, and audio.
How much Chip RAM do different Amiga models have?
Amiga 500: 512KB (expandable to 1MB). Amiga 500+/600: 1MB. Amiga 1200: 2MB. Amiga 2000/3000/4000: 1MB or 2MB depending on revision. 2MB is the maximum for ECS/AGA chipsets.