SLI and Crossfire. What are these and when we need them.


SLI and Crossfire , Mainly there are two main brands producing graphic cards.

  1. Nvidia
  2. AMD

You can get either AMD or NVIDIA graphics card in you PC. There two words SLI and Crossfire are also related to these two brands. SLI can be Done with NVIDIA and Crossfire can be done by AMD.

Usually we saw PC’s with dedicated graphics cards. Do you know we can install more than one graphic card in a single PC to make them work collectively to increase the graphics performance for high graphic intensive tasks. Now lets study these two terms separately .


This technology is developed by Nvidia (GPU manufacturer). SLI refers to Scalable Link Interface. This name is used to market their technology of connecting more the 1 graphics card together.

This is Basically a parallel processing algorithm for graphics intensive tasks.We can connect up-to 4 graphic cards in Nvidia SLI .These SLI setups consist of :

  1. 2-Way
  2. 3-way
  3. 4-way
  4. Quad

Now you will say QUAD and 4-way is a same thing. Read below i will describe all these separately.

2-Way :

SLI generally results in a 60-90% increase in framerate (though this is typically only while running a 2-way setup).

This is due to scaling, which does best in two-GPU setups (not necessarily two-card setups).

3-way and 4-way :

Adding more GPUs allows you to get more performance, but the gains diminish rapidly.

In addition, having more than 1 GPU will almost always require you to have a high-end CPU (at least a normal quad-core i7), and 4-way/Quad SLI will require a very high-end CPU (hex or eight-core i7, or a Xeon).

If you’re using a simple 2-way SLI setup, a normal unlocked quad-core i7 will do fine (the x700K variants). Be sure you have enough power for the additional card, and proper airflow/cooling.

It’s also recommended to have proper cooling for the CPU, as there will be a substantial load on the CPU while running SLI.

This is because when you add more GPU, you want that additional GPU to run freely, and not slow down.

This means having a powerful CPU to keep feeding the GPU information, as a lack of information will result in lag, stuttering, poor quality, and potentially crashing.

4-Way vs Quad SLI :

The difference is in 4-way we are using 4 GPU’s while in Quad SLI we are using two quad GPU’s.

Quad SLI has little advantage over 4-way is Quad-SLI scales better, as there are less cards to manage


Dual GPU
Dual GPU Nvidia card


This is exactly same as SLI just the difference is this is developed by AMD. This is also same process to connect more than 1 graphic card at same time to do graphics parallel processing.

AMD crossfire

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