You need to use NVIDIA's SLI function, the full name is Scalable Link Interface (also called Speed Force), which is a patented technology of NVIDIA. It uses two, three and four PCI-E graphics cards of the same model on a motherboard supporting dual, three and four PCI Express X 16 through special interface connection.
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In theory, SLI technology can double the graphics processing capacity. In practical application, except for a few tests, the graphics performance in actual games can only be improved by about 80%. In some cases, there is no performance improvement at all, and there are not many games that can support SLI well. Of course, with the improvement of the driver, the practicality of SLI is gradually improving.
When two graphics cards are used to form a SLI configuration, these games using GPU can achieve up to 2 times performance improvement. Most of today's hottest games and new generation games belong to this type. However, some applications (usually older applications) are still limited by factors other than GPU processing power.
Baidu encyclopedia -SLI