EDIT: This may also work for ATI HD3870 ! (not 3870X2!)
HINT: new motherboard - same gpu with gfxstr - no screen?!
It seems to be that an working gfxstring may NOT work anymore if you use the same gpu in an new/other mainboard!
Also shared gfxstrings for an gpu may not work in YOUR enviroment! Can be that the new mainbaord has other ID for the PCIe Slot. Wrong PCIe ID in "used/shared" gfxstring may result also in no screen,
So this easy EFISTUDIO tool is great to get really your own gfxstring.
Very usfull for those 3850/3870 users which get scrambled / no screen at all with their try&error downloads of ATI3850 packages shared around.
Whats TRIAKIS ?
Its an modded Framebuffer (i dont know who made it) , which is used insted of the LAMNA.
TRIAKIS Framebuffer plugin is in the ATINDRV.KEXT which is included.
To use this Framebuffer, it must be called /linked by the gfxstring (or, not recommended by the injectors like NATIT.KEXT)
The orig. EFISTUDIO only has an 3850 entry with LAMNA link, not the TRIAKIS.
So i made this set of EFISTUDIO + fitting ATINDRV.KEXT with TRIAKIS framebuffer plugin inside.
!! Start EFISTUDIO, select the ATI 3850 TRIAKIS entry for 3850/3870 users - perhaps good to remove an extisting(not working) gfxstring before!!
!! If you made gfxstring (in boot.plist) you MUST remove all injectors (NATIT.KEXT, NVCRUSH.KEXT) !!
!! Before reboot, install the ATINDRV.KEXT with Kext Install Helper (or make by cli commands rights/owners are OK, all must be root:wheel) !!
!! Before reboot you should remove extensions.mkext or boot once with bootflag -x (safe mode - rebuilds extensions.kext) !!
DL below includes:
1. EFISTUDIO with ATI HD3850_TRIAKIS gfxstr with Triakis insted of Lamna strings
2. fitting ATINDRV.KEXT (TRIAKIS) for gfxstr above
LINK: NVINSTALLER has new 10.5.5 dev ATI drivers !!!