Hey Plox, could we please get some system specs as well as details on that GPU ? Updating drivers is simple.
1. download your new drivers from nvidia.com if using nvidia, alternatively go to ati.com
2. uninstall your current drivers by going to control panel-> hardware and sound-> device manager -> open the drop down menu for display adapters -> right click to uninstall
3. reboot
4. install new drivers
note: some/most people will recommend using driversweeper/cleaner to make sure all the old drivers are completely gone. I do this every once in a while, normally only when i see a problem in-game such as glitches/crashing or if the driver update does not fix a problem. I have only used Nvidia, so i cannot say how much of an effect this will have on ati products.