Some HPs lock up on the Nvidia 750 model. But your post is incomplete so no one can check for issues or the power supply issue.
I'm trying to install a graphics card to my computer. I was originally running the computer off of intergrated graphics. The graphics card goes into the PCI express slot fine and when I power on the computer the fans on the graphics card turn on. The hardware on the computer is a
GTX 750 Ti
INtel i3 2100
The computer acts like it wants to turn on as it boots up it displayed the usual start up screen but then stays on the screen and acts like its froze ( this is while the graphics card is outputting the video ).
I've tried taking out the ram and putting it back in but to no avail.
If you need any more information I'd answer anything I need help.

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