The graphics card need a 300W @ 22A. Your PSU has enough wattage, but does it have the needed amperage?
What is the make and model of this computer?
What is the make and model of the PSU?
Please download and install Speccy
to provide us with information about your computer. Clicking on this link will automatically initiate the download.
When Speccy opens you will see a screen similar to the one below.
Click on File which is outlined in red in the screen above, and then click on Publish Snapshot.
The following screen will appear, click on Yes.
The following screen will appear, click on Copy to Clipboard.
In your next post right click inside the Reply to Topic box, then click on Paste. This will load a link to the Speccy log.