Loading Images 50 at a time

I have a page, I want to load up to 900 DIV's (containers for images). The number of DIV's is unlimited but would likely only every be a maximum of 1,000 - 2,000 and even this is extremely unlikely.

I want this page to load with all DIV's initially.

I want images to load, 50 or a 100 at a time and loaded into the appropriate DIV for that image. Not based on the user scroll but just one after the other. Using AJAX I imagine.