PDF files are simply everyone's headache to start with. When you think you can simply scroll through page after page... surprise it's still downloading more information. The simple tip is to simply let it sit for a minute or so and then you use the arror button to go through page after page or simply download the complete pdf file to a folder and view it much faster on the drive!
Well that's if you have the option to save the file in question to a folder and not limited to online viewing only like many are. Urgh!