vDGA mode without View, but XMing remote access on RHEL6.7 host

I’m making some research on VMware vDGA mode for Linux RHEL 6 based VM, accessed via X client/server remote SW (XMing)
I don’t plan to use View since my VM is a linux one and the current view agent for linux is really at it’s early stage.

My HW is a Dell server equipped with 2 Nvidia boards, including a K1 grid one, running an ESXi 5.5u2.

vSGA mode works fine so far, direct rendering being enabled, but strangely with poor glxgears results for RHEL6.7 (about 600 fps) despites 3D acceleration and rendering options set, while glxgears is about 3000 fps for same config with RHEL7
Because RHEL 6 is a requirement to me, I gave a try to vDGA mode to bring up RHEL 6 performance to the RHEL7 one.

I have then started to play with VMware vDGA install on RHEL 6.7, pass thru ok, driver install ok, basic xorg.conf file generartion, and I’m stuck on booting again the machine.

Here comes my trouble since the VMware doc for vDGA on RHEL6.6 is assuming View.
When I start the X mode again, I got a message "no screen found".

Does anyone of you guys have experimented this configuration and would help me with some advices/tutos?

I can’t believe this doesn’t work without View

Help appreciated!