Black Screen after installing Nvidia Geforce GT 640

[mrjohnwatts]

I have just encountered an issue after installing a brand new Nvidia Geforce GT 640. On booting up I get the white screen with the apple logo, then the screen goes black, the computer has booted because if I press a key on the keyboard I get a beep sound.

I have tried connecting using HDMI and VGA, but I don't have a DVI cable.

If I boot with the HDMI cable plugged into the MOBO instead of the GPU then it boots up but the screen is all fuzzy.

Any ideas?

 

[mrjohnwatts]

False alarm - sorry folks, GraphcsEnabler=No did the trick.

 

[diedo]

dude did you connect it to a VGA Monitor ?

 

[mrjohnwatts]

No I am using a monitor with HDMI. Sometimes it boots fine, sometimes I get the black screen and have to reboot with the GraphicsEnabler=No bootflag.

If anyone could suggest a way to avoid the black screen that would be great, if not then i'll just carry on having to use the bootflag.

 

[helmerpiloto]

see this one:
http://www.tonymacx86.com/general-h...ce-640-working-yosemite-booting-problems.html