B550m Pro4 - No Video

Hello
   I finally got almost all the parts together for my new build. I'll get my new video card in a week or two, but I've got a couple to use until then.
   
   Parts are:
     Asrock B550m Pro4 motherboard
     
     AMD Ryzen7 3700X processor
     
     G.SKILL Ripjaws V Series 32GB (2 x 16GB) 288-Pin DDR4 SDRAM DDR4 3200    (PC4 25600) Desktop Memory Model F4-3200C16D-32GVK
     
     RAIDMAX HYBRID 2 RX-730SS 730W ATX12V V2.2/ EPS12V SLI Ready CrossFire Ready Modular Power Supply

     The 2 temporary video cards I have are both Radeon 7850 cards. One is a MSI R7850 Twin Frozer 2GD5/OC, and the other is a Sapphire HD7850 2G GDDR5. Both cards have 6 pin PCI-E connectors.

     The video card I'm going to get is the MSI Radeon RX 5500 XT DirectX 12 RX 5500 XT MECH 8G OC 8GB 128-Bit GDDR6 PCI Express 4.0 HDCP Ready Video Card.

     I put everything together and when I turn it on, I have no video.

     Things I've tried:

   Reseated the 24 pin motherboard connection (more than once).

   Reseated the CPU 8 pin connection (more than once).

   Reseated the PCI-E connection (more than once).

   Switched out the power supply with a 650w Thermaltake (made no difference).

   Pulled one of sticks of memory out, and swapped the other thru all 4 slots, switched sticks and tried all 4 slots, tried the sticks in A1 and B1, and also tried them in A2 and B2.

   Removed the fan and processor chip, cleaned off old thermal paste, put new, and reinstalled.

   Ran the video cable from monitor to both the integrated output ports that I have cables for (VGA and HDML), along with hooking up to the HDML ports on the video cards. I've gone back and forth with both temporary video cards numerous times, and tried them in both PCIE1 and PCIE3 slots.

   Disconnected everything not necessary for booting (CDrom, M-2 drive), and tried it with and without a SSD that I had sitting around.

     
     Post Status Checker leds are not lit after it goes thru boot process, and I get one beep when done. Everything seems to be working, but no video.


     Am I missing something obvious, or does anyone have any other ideas I can try.


     Thanks for any help.
        Dale

   Thanks for the reply.

     I've already tried both of the cards in PCIE1 (the upper slot) and PCIE3 (the lower slot).


     Dale

I should be able to run a VGA to VGA cable from the monitor to the D-Sub port on the IO panel, right?