Question Building a new PC, fans spin but there's no display ?

Apr 8, 2021
What Matters ----------------
Building a new PC of new and current pc's parts
When I press the power button or short the power the fans spin fine but no display

My Story ---------------------- (can Skip)
My Current Pc is a Prebuilt ROG G20 CB with an i7-6700 and an added GTX 1080. Its a terrible case, It forces you to use one specific motherboard with laptop Ram and 2 external 230w power supplies. With no real upgradability I was given an out, my brother was moving cases and handed down to me a Dr.Zabber's Sentry 1.1 Case, DDR4 Ram and a CPU fan. This required me to get a new motherboard and Power supply and I would just move over my CPU, GPU and Hard drives. So I purchased a H310CM-ITX/ac motherboard and a Corsair SF600 Power Supply on amazon. I put all the components together and when I turned it on the fans would spin for a half second then everything would turn off. Found two bent CPU socket pens, Bent them back perfectly but with no avail, so I ordered a new one. Come to find out my current CPU (i7-6700) isn't compatible with the motherboard I bought. So I decided to upgrade my CPU and I bought a i7-9700. With the new CPU in, the fans spin but no display. Apparently the H310CM-ITX/ac motherboard is only compatible with a 9th gen CPU after a BIOS update (p4.00). However a sticker on the BIOS chip says p4.10, being the most up to date BIOS, I have no way of knowing if this sticker is correct, and if it is wrong I have no way of updating it (amazon reviews say it's up to date). I've Tested everything I can think of (see down below) and I'm not sure why it still won't post. I'm currently working on these components out of the case in a test bench-like setup.

Motherboard: H310CM-ITX/ac (Brand New) NO POST CODES
CPU: i7-9700 (Brand New)
RAM: 2x Crucial 8GB DDR4 2400 UDIMM (Used, Not used in a while)
PSU: Corsair SF Series SF600 (Brand New)
SSD: SK Hinix 250GB (Boot Drive in Current PC)
GPU: GTX 1080 (Works Fine In Current PC)

What I've Tested -------------
I'm almost certain I don't have Bent CPU socket pens. I know the Monitor/Display works, I've tried Integrated Graphics and the GPU, HDMI and Display for Both. I've tried with and without GPU connected. I've tried with an SSD, M.2 and without anything to boot from. I've tried both Sticks of RAM one at a time in the first slot. A24-pin and 8-pin connections Secure. No real possibility for a short. Resetting the CMOS did nothing. I've Used both Stock PSU cables and custom ones. Can't Flash update BIOS as it doesn't have a Flash Bios Button. I've tried all combinations of with and without certain nonessential components.

I have no reason to believe the ram or the power supply are dead and as far as I know the CPU is compatible with the motherboard.
Just Bought a Motherboard speaker will be here Friday, I assume this will allow me to hear post code beeps?
Last edited:

Vic 40

Tried breadboarding? Take the motherboard and psu out of the case, put it on the box it came in and use one stick of ram, connect monitor to the motherboard video output, see if it gives the bios. Out of the case to make sure you have no strange connection with the case itself. Only use the stock psu cables.

Guess you need a riser cable with that pc case, maybe test if that is working okay as well.

In the end might you have a dead motherboard, but symptom sound like there could be a short as well.