Aspire GX-781 Why is my PC not booting up?

I have the Aspire GX-781 with the i7 7700 and I recently bought a 6650xt to change the old gpu that I had. But, the PC isn’t booting up, I have connected the power cables into the gpu and the hdmi cable, the PC starts, I get the startup display but it doesn’t boot up, it just stays in the boot up screen and doesn’t boot. I have already changed PSU to a 650w but still nothing.

[Edited the thread to add model name to the title]