What happened?

I found a bug on the 1024x768x16 packed pixel video mode the 4-planar mode works just fine.

Here is some screenshots:
The test program utility:

1024x768x16 Packed pixel modes:

Taken from the ATI setup disk:

Windows 2.11/286 with the 1024x768 16 colors. Here the screen is distorted like the in the setup test program:

.

On the other hand, the 1024x768 16 colors work just fine on Windows 3.1, but maybe is using the 4-planar video mode:

Also according this site: https://en.wikipedia.org/wiki/ATI_Wonder_series#VGA_cards.

1. The ATI EDGE-16 is limited to 256kb of VRAM, the Wonder 16 is the only 18800 chip based card that support 512 Kb.
2. The ATI Charger 28800-5 supports up to 512 Kb, only the XL/XL-24 supports 1 Mb.

The XL-24 Win 3.1 drivers works fine on the Charger but of course the higer resolution modes are not supported.

Configuration file

[ATI 28800-5 (ATI VGA Charger)]
memory = 1024

[Sound Blaster v2.0]
base = 0220
mixaddr = 0000
irq = 5
dma = 1
opl = 1
cms = 0
receive_input = 1

[General]
vid_renderer = qt_software
vid_resize = 1
enable_overscan = 1
rctrl_is_lalt = 1

[Machine]
machine = spc6000a
cpu_family = i386dx
cpu_speed = 25000000
cpu_multi = 1
cpu_use_dynarec = 0
fpu_softfloat = 0
time_sync = local
mem_size = 4096

[Video]
gfxcard = ati28800

[Input devices]
mouse_type = msserial

[Sound]
sndcard = sb2.0
fm_driver = nuked

[Network]
net_01_link = 0
net_02_link = 0
net_03_link = 0
net_04_link = 0

[Ports (COM & LPT)]
lpt1_device = dot_matrix

[Storage controllers]
hdc = ide_isa
cassette_mode = load

[Hard disks]
hdd_01_parameters = 17, 15, 900, 0, ide
hdd_01_fn = 
hdd_01_vhd_blocksize = 1024
hdd_01_speed = 1992_3600rpm
hdd_01_ide_channel = 0:0

Operating system

Windows 10 22H2

CPU

i5 4210U

86Box version

4.1.0.5290

Build architecture

Windows - x86 (32-bit)

Build type

• New recompiler
• Debug build

Download source

Official website (Jenkins, GitHub)

Additional context

No response