Figuring out whether a graphics card is compatible with a motherboard often involves figuring out whether you have an open slot on your motherboard that matches the card you want. You also need to take into consideration whether it will physically fit inside your tower and not interfere with the rest of your hardware. Additionally, you can use online tools to check what is specifically compatible with your current build.
Fitting in Slot
Before buying and installing a new card, you'll need to make sure you have an open slot on your motherboard that matches the video card you want. There are a few different types: PCI-e, AGP and PCI. The slot type of the graphics card can be found on its product information page or its information booklet, and you can find out which slots your motherboard has by searching online for its specific model.
Fitting in Tower
Even if the graphics card you want fits into a slot on your motherboard, it may not have room to fit inside your tower. Smaller motherboards and towers may not be able to hold larger graphics cards. If your peripheral card slot is right next to your RAM or heat sink, for example, a new graphics card might be blocked from fitting. If you are concerned, check how big the card is and measure inside your tower. In some cases it might be a tight fit, but as long as you aren't bending any parts or touching them together, it should work fine.
Running With Other Hardware
Even if the graphics card fits with your motherboard, you need to make sure it can run with your other hardware. If you are installing a significant upgrade, make sure that your power supply unit is powerful enough to handle it. If the wattage on your current power supply isn't enough for a more powerful card, it may not work even if it fits correctly. If a card fits and has enough power it will often work, but when upgrading older computers it's a good idea to check compatibility with your older parts as well, such as your CPU.
Use Compatibility Tools
There are a few different ways to check the compatibility of hardware you want with the hardware you already have. You can use PCPartPicker to enter the hardware you currently have installed and see everything that is compatible with it. If you want additional help, PCPartPicker lets you link to your build so you can ask others for help. You can also look up the cards you want on Newegg; Newegg's product listings will take you to the manufacturers' websites, which will often tell you where you can install their cards.