However, there are thumb drives that will speed up the boot process but that is it. If you want to speed up games etc you will need an internal solid state drive. They are not cheap but never have to be defragmented. I use one for my C drive but I am very careful about what gets installed there. It speeds up boot up and will speed up anything on it. I usually have only one or two games on it at a time. Internet traffic will still affect performance. a better video card will also help. try to get one with at least one gig if you can afford it. try not to go below 500 meg. also do not get one that uses shared memory.
Using your USB mass storage device while loading an online game will only make the loading process to go slower. This is because; the USB drivers and programs will be competing for processing power with the game.