Including AGP/PCI-E 16X power supply of power supply and motherboard, if the graphics card does not get enough pure current, the screen may also appear.
The solution is to disconnect the CD-ROM drive, independent sound card and other unnecessary hardware to reduce the load of the whole machine and try again.
There are many reasons for graphics card problems. It is possible that the graphics card BIOS is defective, which can be solved by refreshing VGA BIOS; It is also possible that the main memory is damaged, which is a common situation.