Screen modes
The Amiga was capable of displaying various screen resolutions. All monitors and TV's of that time had a picture aspect ratio of 4:3 but the pixel aspect ratio varied grately. The ratios in the lists are pixel aspect ratios and the are rounded to the nearest neighbour. In reality PAL pixels are a tiny bit wider than they are tall (16:15) and NTSC pixels are a bit taller than they are wide (8:9).
OCS (Original Chip Set - released 1985)
The hardware that was used in the first generation of Amigas still very close to the original concept of the Amiga being used as a video games console. For that reason the screen modes where tied very closely to the television standards NTSC and PAL that where in use at that time. This also meant that the screen modes varied depending on what type of Amiga you had and where you had it.
| Name | Resolution | Colors | Depth | Pixel Aspect Ratio |
|---|---|---|---|---|
| NTSC - 15kHz / 60Hz | ||||
| LowRes | 320x200 | up to 32, EHB, HAM | 12bit | 1:1  |
| LowRes Laced | 320x400 | up to 32, EHB, HAM | 12bit | 2:1  |
| HiRes | 640x200 | up to 16 | 12bit | 1:2  |
| HiRes Laced | 640x400 | up to 16 | 12bit | 1:1  |
| PAL - 15kHz / 50Hz | ||||
| LowRes | 320x256 | up to 32, EHB, HAM | 12bit | 1:1 |
| LowRes Laced | 320x512 | up to 32, EHB, HAM | 12bit | 2:1 |
| HiRes | 640x256 | up to 16 | 12bit | 1:2 |
| HiRes Laced | 640x512 | up to 16 | 12bit | 1:1 |
ECS (Enhanced Chip Set - released 1990)
The enhanced chip set was released with several small improvements over the original chip set.
New screen modes where added to support higher resolutions offered by multisync monitors but at the same time sacrificing color depth.
Technical limitations also limited the usefullness of many of these new modes as most had either very extreme pixel aspect ratios or were limited to very few colors.
The reason for this was possibly the attempt to squeeze addition features out of the original chip set design without changing to much on the chip.
| Name | Resolution | Colors | Depth | Pixel Aspect Ratio |
|---|---|---|---|---|
| NTSC - 15kHz / 60Hz | ||||
| Super-HiRes | 1280x200 | up to 4 | 6bit | 1:4  |
| Super-HiRes Laced | 1280x400 | up to 4 | 6bit | 1:2  |
| PAL - 15kHz / 50Hz | ||||
| Super-HiRes | 1280x256 | up to 4 | 6bit | 1:4 |
| Super-HiRes Laced | 1280x512 | up to 4 | 6bit | 1:2 |
| Multiscan | ||||
| Productivity | 640x480 | up to 4 | 6bit | 1:1 |
| Productivity Laced | 640x960 | up to 4 | 6bit | 1:2  |
| A2024 NTSC | ||||
| 10Hz | 1024x800 | up to 4 | 2bit | 1:1  |
| 15Hz | 1024x800 | up to 4 | 2bit | 1:1 |
| A2024 PAL | ||||
| 10Hz | 1024x1008 | up to 4 | 2bit | 1:1 |
| 15Hz | 1024x1008 | up to 4 | 2bit | 1:1 |
| Euro36 - 36Hz | ||||
| LowRes | 320x200 | up to 32, EHB, HAM | 12bit | 1:1 |
| LowRes Laced | 320x400 | up to 32, EHB, HAM | 12bit | 2:1 |
| HiRes | 640x200 | up to 16 | 12bit | 1:2 |
| HiRes Laced | 640x400 | up to 16 | 12bit | 1:1 |
| Super-HiRes | 1280x200 | up to 4 | 6bit | 1:4 |
| Super-HiRes Laced | 1280x400 | up to 4 | 6bit | 1:2 |
| Euro72 - 72Hz | ||||
| Productivity | 640x480 | up to 4 | 6bit | 1:1 |
| Productivity Laced | 640x960 | up to 4 | 6bit | 1:1 |
| Super72 - 72Hz | ||||
| HiRes | 400x300 | up to 16 | 12bit | 1:1 |
| HiRes Laced | 400x600 | up to 16 | 12bit | 1:2 |
| Super-HiRes | 800x300 | up to 4 | 6bit | 2:1 |
| Super-HiRes Laced | 800x600 | up to 4 | 6bit | 1:1 |
AGA (Advanced Graphics Architecture - released 1992)
The AGA chipset was the first real improvement over the original chipset. Further screen modes where added, the color palette was extended to 24bit and resolutions with up to 256 colors. All resolutions could now be used with all color modes.
| Name | Resolution | Colors | Depth | Pixel Aspect Ratio |
|---|---|---|---|---|
| DblNTSC - 31kHz / 60Hz | ||||
| LowRes | 320x200 | up to 256, EHB, HAM, HAM8 | 24bit | 1:1 |
| LowRes No Flicker | 320x400 | up to 256, EHB, HAM, HAM8 | 24bit | 2:1 |
| LowRes Laced | 320x800 | up to 256, EHB, HAM, HAM8 | 24bit | 4:1  |
| HiRes | 640x200 | up to 256, EHB, HAM, HAM8 | 24bit | 1:2 |
| HiRes No Flicker | 640x400 | up to 256, EHB, HAM, HAM8 | 24bit | 1:1 |
| HiRes Laced | 640x800 | up to 256, EHB, HAM, HAM8 | 24bit | 2:1 |
| DblPAL - 31kHz / 50Hz | ||||
| LowRes | 320x256 | up to 256, EHB, HAM, HAM8 | 24bit | 1:1 |
| LowRes No Flicker | 320x512 | up to 256, EHB, HAM, HAM8 | 24bit | 2:1 |
| LowRes Laced | 320x1024 | up to 256, EHB, HAM, HAM8 | 24bit | 4:1 |
| HiRes | 640x256 | up to 256, EHB, HAM, HAM8 | 24bit | 1:2 |
| HiRes No Flicker | 640x512 | up to 256, EHB, HAM, HAM8 | 24bit | 1:1 |
| HiRes Laced | 640x1024 | up to 256, EHB, HAM, HAM8 | 24bit | 2:1 |