Description: This article contains some of the most frequently asked questions about SLI and Crossfire from Winter of 2019.

Q: What are SLI and Crossfire?
A: SLI and Crossfire are technologies that allow you to use multiple graphics cards to enhance the display performance of one or more monitors.

Q: What is the difference between SLI and Crossfire?
A: While there are a few differences between SLI and Crossfire, the main thing to know is that SLI is NVIDIA and Crossfire is AMD. Otherwise, they are tow different approaches to achieve a similar result.

Q: Can I SLI or Crossfire with two different GPUs?
A: No, all the GPUs in your SLI or Crossfire configuration must be the same. For example, an NVIDIA GTX 1070 can only SLI with another NVIDIA GTX 1070.

Q: Can I have more than two GPUs in SLI or Crossfire?
A: Yes. You can have as many as four GPUs in SLI or Crossfire if your motherboard and processor can support them. Three and four way configurations can add a lot of rendering power for 3D applications. Video Games will see some improvement with three way SLI over two way but will not benefit from three way Crossfire.

Q: How can I tell if my motherboard supports SLI or Crossfire?
A: Some boards will show support for SLI, Crossfire, or multiple GPUs on the box, but the best way to tell is to check the manufacturer specifications.

Q: How many displays can I run in SLI or Crossfire?
A: SLI and Crossfire will support a maximum of two monitors, however you can add additional monitors by installing GPUs that are not part of your SLI or Crossfire configuration. These additional GPUs must be different from the GPUs in you SLI or Crossfire configuration. For example, if you have two GTX 1070 cards in SLI, you can support additional monitors on a GTX 980, but not another 1070.

Q: Do I need special hardware for SLI or Crossfire?
A: SLI requires an SLI Bridge, which directly connects the GPUs to each other. AMD Crossfire does not require any extra hardware.

Q: What is Alternate Frame Rendering AFR?
A: AFR is when frame rendering is cycled through multiple GPUs. If you have two way SLI or Crossfire, each card would render every other frame, only either odd or even, letting the other card handle the rest. This gives the card twice as much time to render and can help prevent tearing, stuttering, or blurring especially when there is a lot of motion.

Q: What is Split Frame Rendering?
A: Split Frame Rendering is when two or more cards are used to render part of each frame. This allows for sharper images at extremely high resolutions but is less advantageous when there is a lot of motion as it can increase tearing.

Q: What is Anti aliasing?
A: Anti aliasing is any of a few techniques used to smooth out jagged diagonal lines. Jagged lines occur because square pixels cannot create smooth curves. At higher resolutions, this effect is easily masked, but at lower resolutions your GPU may have to disguise the jagged lines by adding shading effects to blend the lines. With multiple GPUs, each card can handle a portion of the anti-aliasing, or one card can be dedicated to anti-aliasing while another card renders the rest of the frame.