I use a 32-bit operating system. While it's true a 32-bit OS can't address more than 3.8 GB RAM it will perform twice as fast compared to a 64-bit OS, since the addresses are half as long and thus faster the read/write. This is why old video games used to load up so fast, 16-bit memory is 4 times faster than 64-bit memory allowing the processor and GPU to blast process even faster, I get 25% more FPS on average using an 32-bit FPS. 32-bit operating systems are the clear winner for anyone serious about gaming.