Big problem Z97 Anniversary boot

[w0lf0.]

Hi all, i have big problem with my MB AsRock Z97 Anniversary, after hours and hours of test i have seen that the Mobo doesn't recognize or block modded bios gpu, i have tried with mine 4x470s and only with the 4° not modded gpu the display work otherwise display has no signal,it is possible? what can i do?
Thanks all

[w0lf0.]

anyone know why that happen?
It's like original bios check of gpu by motherboard?

[w0lf0.]

i tested again and its the result:

-only the gpu with mod bios connected to monitor>>computer boot but no signal on display
-stock gpu and modded gpu >> computer boot with stock gpu connected on monitor and display but the bios of mobo and win10 doesn't show the modded gpu
-only stock gpu >> computer boot and all work well

 

with previous mobo modded gpu was ok, new mobo (asrock z97 anniversary) doesn'e see it