Stupid question, but you have got all power management and sleep functions turned off? I run my monitor from the iGpu, and hdmi dummy plugs on the Pcie cards. I had a similar issue when I first built my rig, turning off all power management, and sleep functions cured it for me.
thank you sir in deed in the bois there was a gpu render power save mode and it was enabled... disabled it and everything is algudz \
thnakyou