[SOLVED] PC goes through POST but no display signal

[henrystone]

Hi,

I've been making a new PC. I'll put my part details at the bottom. As the title says, my PC "boots" where the fans, GPU, CD drive, and everything powers on. I get a single, short POST beep to signal that everything is ok. However, I only get a black screen with no motherboard logo or BIOS popping up. In fact, none of the monitors I've tried, and with different video cables, have been able to receive any signal from the PC. I have spent more than a week researching other posts on this site and others with no luck. I ordered a different motherboard and have the same problem. Both motherboards are confirmed AMD 3rd-Gen Ready and have the corresponding sticker on the box. The keyboard can light up the caps lock and num lock keys.

What I've done so far: Resat everything. Attempted barebones startup with one ram stick, CPU, and GPU. Used different monitors with HDMI or DVI-I cables, with both motherboard outputs or GPU outputs. Ran computer for an hour on both motherboards, to see if it would change anything. I've used a different PSU as well. I verified motherboard is installed correctly with the proper standoff screws. I can order replacement parts, but POST still gives single, short beep which signals the parts are working. I have cleared CMOS as well.

What am I missing? Thanks.

Parts:
CPU: AMD Ryzen 5 3600X
GPU: XFX Radeon RX 580 GTS Black Edition
PSU: EVGA White 500W, Black
RAM: Corsair Vengeance LPX 2x16GB 3200MHz C16 DDR4
SSD: Samsung 970 EVO 500GB M.2 NVMe with V-NAND
Case (if it matters): Rosewill ATX, Nautilus

Two Motherboards I've Tried:
Gigabyte B450M DS3H
ASUS Prime B450M-A

 

[rocktalkrock]

Have you checked the CPU for bent pins?

 

[InvalidError]

Motherboard video outputs are not going to work since the Ryzen 3600 has no video circuitry to drive them with, only APUs do.

If caps/num toggle the keyboard LEDs, then the PC is indeed working. However, you should be getting additional POST codes if the CPU is failing to find and initialize the GPU, usually eight beeps for VGA failure unless you configured the BIOS to ignore it.

Make sure you have a known-good monitor, a known-good cable and that they are connected and powered up before you turn on your PC. If the GPU fails to immediately detect the monitor at boot for any reason, it may choose to route the boot screen to the wrong output.

If that still does not help, you may want to borrow a different GPU.

 

[Mr.Spock]

If you have the motherboard boxes make sure the Gigabyte has bios rev. F40+ for Ryzen 3600 support? v1201 for the Asus?

 

[henrystone]

I have checked the CPU for bent pins, and it's all good. I used a different GPU, but I guess that one wasn't compatible either. I did, however, try a third GPU which worked and got the system running, updated all of the drivers, and now my XFX GPU works well.

Thanks everyone.