Intermittent Black Screen on Boot - ML 10.8.5

[tmhanser]

I'm having trouble with my Dell Optiplex 960, running ML 10.8.5.

The OS is update and the machine runs remarkable well, despite these black screens I get on boot. I suspect the graphics driver is not being loaded properly - can anyone verify this?

Normally when I boot up, the graphics card fan is blowing at 100%, until the driver loads (I assume) and then it idles down. This is also the point that the desktop appears.

But often I get a black screen, no desktop and the fan continues to run at full speed. The current graphics card is an nVidia GeForce 8600 GTS, 256 MB RAM.

I have not installed any nVidia drivers from their site, as there isn't one available for ML 10.8.5.

I have GraphicsEnabler=Yes set in folder Extra/org.chameleon.Boot.plist.

Would it help to disable the onboard graphics in the BIOS?

Can anyone comment on this problem? Would a different and newer model card and driver resolve this?

Thanks.

 

[aschwalb]

I have the same problem (I think) When I power on the computer it boots but I get black screens. I power off (forced off) then power on and it boots fine. It almost never (maybe always) boots the first time. I also have a Nvidia GTS 8600 256... Otherwise my system runs great. I have disabled the onboard video via the bios and did not have this problem when running snow leopard 10.6.8.

Thanks