Write down your system specs, including the CPU, power supply, case size, and current graphic card, as well as the make and model of your current monitor. Look for a graphic card for gaming that is compatible with these specs and will fit inside the computer case. Keep in mind that the older your computer system, the less likely it is to be compatible with even low-end 4K graphic cards. In that case, it might be more economical to purchase a new gaming system. Even last year’s models will be a huge step up in graphics performance at a bargain price.