I hope I don't regret getting involved in this, but here goes anyway ...
Sorry Odlschool, but neuro is correct. Your calculation of 3 x (800 x 600), which totals 1 440 000, is correct, but is not equal to (3 x 800) x (3 x 600) which totals 4 320 000 pixels, which equals 9 x (800 x 600).
This is a single picture being rendered across 3 monitors, with a height of 600 and a width of 2400 (3 x 800). The total number of pixels being rendered in this picture is 600 x 2400 (total height x total width), which equates to 1 440 000 pixels. This is close to 1280 x 1024 (1 310 720 pixels), and quite a bit less than 1920 x 1080 (2 073 600 pixels).
Hope this helps
