GTX 285 Black Screen

[sampledi]

I've searched the forum but I haven't noticed that anybody have issue like this.

 

Supermicro X8DAE motherboard

Dual Xeon (8 cores, 16 threads)

NVIDIA Geforce GTX 285, 2GB VRAM (DVi, HDMI, VGA)

MacPro 5.1 Smbios definition

 

I have installed Yosemite W/O any major issues but than came to a problem that I can not solve. What ever I do, if I boot normally, I get black screen/s. And I'm not talking about "DVI Signal Not Found" - I get black screen with cursor over it. I can move the cursor but that's it. (this happens after boot sequence, before login screen should come up)

 

I can boot to Desktop with safe boot (-x) or with nv_disable=1, so I guess this is GPU issue

 

What I have tried by now:

- all possible different boot loaders (Chameleon, Clover)

- default OS X driver and NVIDIA web driver (nvda_drv=1)

- combination of different boot flags

 

Does anybody have any idea what else could I try?

 

Thank you in advance.