We're often asked which card is compatible with a given motherboard. A lot of the time, the answer is "It depends." If you want to be sure about using one or another graphics card on your motherboard, here are some guidelines.

To make sure a new graphics card will work with a PC, you’ll need:

  • On your motherboard, there's a PCIe x16 slot
  • In this situation, you'll need adequate space for clearance.
  • Power supply with both 8- and 6-pin PCIe Graphics (PEG) connectors
  • CPU and RAM that is fast enough not to be a huge bottleneck

If you're on the market for a new motherboard (or new PC) and wonder if your current or next graphics card will be compatible, here's what to look for:

Space in your case to accommodate the length of the card. Also consider how it might overlap with other cards in multi-GPU systems, or with CPU coolers. Note that some cases have extra room at the bottom specifically for accommodating larger cables and connectors. With only two PCIe slots, SLI/CrossFire isn't supported anyway. PCI Express x16 3.0 is required. Slots are backward compatible, so v2.1 cards will work too but they'll operate at reduced performance levels there just as they do when used on older 2. x motherboards.

This is most likely the board. The only question is whether it has enough PCIe x16 lanes. If you regularly play games, yes. Graphics cards are agnostic about what they plug into, so this is an either/or situation - there's no advantage to using a more powerful card on a lower-spec board. You can buy whichever card you want and upgrade later if your motherboard doesn't have enough lanes for the next generation of cards coming out in 2017+.

How Much Space in Your Case? 

Although there may be some differences in the way graphics cards are compared to other components, they're in the same class of technology and compete against one another. The newest video cards can't fit into every old PC with a PCIe x16 slot because of different hardware demands. For example, you'll struggle to squeeze a 320mm long graphics card into a case that only has space for a 270mm card. Many small PCs will be limited in what they can accommodate, and pre-built systems frequently fall into this category.

Computer cases with a "hold-down" design - where the PCIe card is secured by a bracket that fits into a slot on the back of the case - can pose problems. If your motherboard has only two PCIe x16 slots, you'll need both of them to be open to using SLI or CrossFire, but that may mean leaving out some other component you were planning on using. On video cards that require power from 6-pin connectors on the motherboard (or plug directly into an 8-pin PCIe connector), there's less than 5mm space between the backplate and capacitors/PCIe slot depending on how far they are offset.

Additionally, we recommend having some wiggle room. Even if you get 300mm of clearance and a graphics card says it's 300mm long, it may be too tight of a fit. Subtracting 20mm from your measurement and buying a card that is shorter than the calculated length should do the trick.

Do You Have The Right PSU? 

Another barrier is the requirement for power. If you have a PC built before 2015, likely, your power supply won't include any 8-pin PCI Express Graphics (PEG) power connectors, which are required on many of today's faster graphics cards. 6-pin PEG connections have been in use longer, but some cheap power supplies still leave them out. If you have a desktop from a major OEM (such as Dell, HP, or Lenovo), you may not be able to replace the power supply for a newer one with the proper 6- or 8-pin connections.

Graphics cards come with power connectors, but you need to know how many and what type. Buy a PSU that has at least 8-pin PEG connections for up to 150W (GeForce GTX 1050), 6+2 pin for 75W (GeForce 1030), and 8+8 pin for 225W (GeForce 1080 Ti). Also, note the PCIe power connector requirements on your graphics card - some don't have any while others require a single connector or multiple ones. Be sure not to neglect the wattage rating either, which is usually higher than the total current capabilities of all connected devices.

Incompatible Cables 

A look at modern video cards shows there's been an explosion of types of cables used on graphics cards. From HDMI to DisplayPort, plus DVI and VGA, it can be a confusing mess for new PC builders.

The most important thing to remember is that if your graphics card needs a specific cable(s) that isn't included with your power supply - or you've upgraded the PSU but haven't also bought all of the necessary cables - you won't be able to use it. To avoid problems, look at both your motherboard and graphics card before installing them in your case and the connections required of the power supply. You don't want to have an option available on one of those components only to find out later that it's not compatible with another choice you made.

Are Your Other Components Good Enough? 

With SLI and CrossFire multi-GPU setups - which are reliant on the PCIe bus for communication between cards - your motherboard must be compatible with them. If you've upgraded to a newer Z170 chipset (even if it has the same number of PCIe lanes as previous generations) you may find yourself limited in how many GPUs you can run simultaneously.

The best single-card solution today is still Nvidia's GeForce GTX 1080 Ti graphics card, but that nameplate alone cost over $700 at launch with most models now available for around $900 or more. The performance difference between 1060, 1070, and 1080 cards warrants consideration of these high prices when you're looking at two sub-$500 graphics cards in SLI/CrossFire, so buyer beware.