What else to do? Asrock H81 Pro BTC 2

I have the following:

1. Asrock H81 Pro BTC 2
   
2. Sapphire 11260-01-20G AMD RX 480 Nitro+ 8 GB GDDR5 Memory PCI-E Graphics Card X5
   
3. Intel Celeron G1820 CPU
   
4. EVGA SuperNova P2 850 W Platinum
   
5. Corsair CP-9020098-UK VS Series VS650 ATX/EPS 80 PLUS
   
6. Multiple power supply connector ADD2PSU
   
7. Crucial MX300 525 GB SATA 2.5-Inch Internal Solid State Drive
   
8. XCSOURCE PCI-E 1X to 16X Mining Machine Enhanced Extender Riser Card Adapter X2
   
9. PCI Express x1 to PCIe x16 Riser Card Flexible Cable 1x 16x X3
   
10. HyperX FURY Series 8 GB DDR3 1866 MHz CL10 DIMM Memory Module - White
    

I am using a Dell monitor which works fine connected to the mining rig via an HDMI/DVI cable.
I have had problems with a previous asrock H81 Pro R1 mobo and bought this one. (this was when I tried to get the fifth graphic card to work). It worked to the four cards and after connecting the fifth, lost the monitor and nothing I did brought them back. I am now inbetween Amazon and Asrock.
So I purchased a R2 of the H81 Pro BTC mobo.
I am now having the same problems with this mobo and I can't understand it as I have tried everything I know.
The problem is simply that no matter which connector I use HDMI or D-sub, I can't get the monitor to display either a Windows 10 or UEFI screen.
I have tried:

1. HDMI between No 1 Graphics Card/TV + HDMI (onboard)/Monitor + D-Sub/Monitor (1 graphic card on)
   
2. HDMI (onboard)/Monitor + D-Sub/Monitor (no cards)
   
3. D-Sub/Monitor (no cards)
   
4. HDMI (onboard)/Monitor (no cards)
   
5. HDMI between No 1 Graphics Card/TV (no cards)
   
6. HDMI between No 1 Graphics Card/TV + D-Sub/Monitor (no cards)
   
7. HDMI between No 1 Graphics Card/TV + HDMI (onboard)/Monitor (1 graphic card)
   

All the while stabbing furiously the Del or F2 key.
I have never got a screen.

Is there any other setting on the mobo that I have missed because I am now thinking that maybe if I purchase the ETHos software, it may work but my brain is telling me that irespective of whether Windows 10 or ETHos, the UEFI should still display to the screen.

Currently, the graphic cards have all been disconnected so I am trying to see if the onboard will work to no avail so I have connected the slot 1 graphic card but I still get no screen.
If this question has been asked and answered before, I apologise. I gave googled to no available. I mean what do you google for? How to connect mobo to monitor or what to do to connect mobo and monitor?
Its just frustrating. Please can anyone help? I am really getting desperate as I still have tons to do because I know there is still a mod to carry out to get the fifth graphic card to work.