This is historically not uncommon at all. Before starting an Operating System and initializing a graphics mode, your PC operates in the simplest display mode available, 80x25 text mode.

The original VGA 80 x 25 text mode (that is still supported by most modern graphics cards) has characters with a resolution of 9x16 pixels per character.

This adds up to 80 x 9 = 720 horizontal pixels and 25 x 16 = 400 vertical pixels.

Note: The character set commonly uses only 8x16 pixels per character. The 9th pixel column is a repeated 8th pixel column. This separates most characters for a nicer visual impression.

This is historically not uncommon at all. Before starting an Operating System and initializing a graphics mode, your PC operates in the simplest display mode available, 80×25 text mode.

The original VGA 80 × 25 text mode (that is still supported by most modern graphics cards) has characters with a resolution of 9×16 pixels per character.

This adds up to 80×9 = 720 horizontal pixels and 25 × 16 = 400 vertical pixels.

Note: The character set commonly uses only 8×16 pixels per character. The 9th pixel column is a repeated 8th pixel column. This separates most characters for a nicer visual impression.

This is historically not uncommon at all. Before starting an Operating System and initializing a graphics mode, your PC operates in the simplest display mode available, 80x25 text mode.

The original VGA 80 x 25 text mode (that is still supported by most modern graphics cards) has characters with a resolution of 9x16 pixels per character.

This adds up to 80 x 9 = 720 horizontal pixels and 25 x 16 = 400 vertical pixels.

This is historically not uncommon at all. Before starting an Operating System and initializing a graphics mode, your PC operates in the simplest display mode available, 80x25 text mode.

The original VGA 80 x 25 text mode (that is still supported by most modern graphics cards) has characters with a resolution of 9x16 pixels per character.

This adds up to 80 x 9 = 720 horizontal pixels and 25 x 16 = 400 vertical pixels.

Note: The character set commonly uses only 8x16 pixels per character. The 9th pixel column is a repeated 8th pixel column. This separates most characters for a nicer visual impression.