Can't get past the Apple gray screen to Install

[unguamoray]

Hey guys!

I'm trying to get a clean install of Mavericks on a desktop and I get no luck.
After using UniBeast to put the Mavericks.app on a 8GB flash drive (USB Legacy mode) I put Multi Beast on the drive, reset all my BIOS settings to default optimised and proceed hitting F12 to the boot menu.
I boot from the flash drive, it goes to Chimera where I can see the USB and my other drives (some of them containing Windows7 or just being NTFS formatted).

From then on anything I do goes to the gray apple screen and then a white flash and goes to black and stays like that no matter how long I keep it. At some point while waiting my computer would turn off (or actually go to some kind of hibernation).

I tried all different boot flags I could find, in different combinations - nothing works for me.
It just seems like I can't get to that Install screen.

Any help would be appreciated!

Motherboard: GA-Z68xp-ud3 F1
Processor: i7-2600K
RAM: Crossair DDR3 1333 two slots with 4GB each (8GB Total)
Graphics: Nvidia GTX 560 ( THE NON TI VERSION )
HDD: WD Caviar Blue 1TB, Seagate 500GB, Seagate SSHD 2TB

Dual monitoring hooked up to the video card (if it matters in any way)

Cheers!

 

[rubycanoe]

Have you tried:

GraphicsEnabler=Yes

 

[unguamoray]

Yes I did. And I did it with combinations of other flags like PCIRootUID set to 1 or 0 etc. etc