New Build Not Displaying Anything and Reboots after 10 Seconds (No POST)

[andynov123]

I just built a new computer. When I turn it on the motherboard LEDs flash and after ten seconds or so, it turns itself off and then a few seconds later turns itself back on and repeats. I took my old PSU from my old computer so I know that's works. Also nothing displays through monitor. I tried plugging HDMI into onboard graphics with no dedicated GPU plugged in and also tried plugging in GTX 1070 and displaying through there, but nothing. I also don't here the POST beep. Here's a link of a video showing the flashing LED I'm referring to. I tried removing CMOS battery and plugging it back in. I reseated CPU. I also checked to make sure PSU wasn't switched to European voltage, but it has no setting for Euro.
https://www.youtube.com/watch?v=m_X-vvSr8HQ&feature=you...


Any help is greatly appreciated

Computer Build:
Motherboard:
ASRock Motherboard Motherboards Z370 EXTREME4
https://www.amazon.com/gp/product/B0763BS899/ref=oh_aui...

RAM:
G.SKILL Ripjaws V Series 16GB (2x 8GB) 288-Pin DDR4 2400 PC4 19200) Intel Z170/X99 Platform Memory F4-2400C15D-16GVB
https://www.amazon.com/gp/product/B017WSVIMG/ref=oh_aui...

CPU
Intel BX80684I78700 8th Gen Core i7-8700 Processor
https://www.amazon.com/gp/product/B07598HLB4/ref=oh_aui...

Chassis
Corsair Graphite Series 760T Full Tower Windowed Case - White
https://www.amazon.com/gp/product/B00P7TPYI2/ref=oh_aui...

GPU
GTX 1070

PSU
SPARKLE Magna R-SPI900GCM 900W ATX12V / EPS12V SLI Ready CrossFire Ready 80 PLUS Certified Modular Active PFC Power Supply
https://www.newegg.com/Product/Product.aspx?Item=N82E16817103032

 

[gdmaclew]

Did you buy and install a motherboard speaker?
If not, that's why you don't hear a POST beep.

Which memory slots did you install the RAM into?

 

[andynov123]

I plugged the RAM into A1 and A2. I also tried A1 and B1. Also I have the "HD Audio" plugged in from the chassis. I thought that would provide the beep? Here's a pic of the plug as reference
https://postimg.org/image/mynsdewel/

 

[andynov123]

Also I just took my old mobo and plugged it into new chassis and it boots to windows fine. So now its confirmed new chassis and PSU are working, which leaves RAM, CPU, and Mobo left.

 

[gdmaclew]

I plugged the RAM into A1 and A2. I also tried A1 and B1. Also I have the "HD Audio" plugged in from the chassis. I thought that would provide the beep? Here's a pic of the plug as reference
https://postimg.org/image/mynsdewel/

The manual on page 17 clearly shows that A2 and B2 are to be used if you have only 2 RAM sticks.

 

[gdmaclew]

I plugged the RAM into A1 and A2. I also tried A1 and B1. Also I have the "HD Audio" plugged in from the chassis. I thought that would provide the beep? Here's a pic of the plug as reference
https://postimg.org/image/mynsdewel/

No. Onboard audio is not where the "beeps" come from.
You must purchase something like this...

https://www.newegg.com/Product/Product.aspx?Item=9SIA2973FN4939&cm_re=motherboard_speaker-_-9SIA2973FN4939-_-Product

You plug it into the motherboard like it shows at the top of page 22...
Power LED and Speaker Header

One end of the connector plugged into +5V, the other into "speaker".

The connector in your picture is a 9-pin HD Audio connector. Connect it to the motherboard like it shows at the bottom of page 23.

 

[smorizio]

pull the gpu and one ram stick. see if you can get onboard video to come on. the video you posted shows the mb trying to post and it failing. that power off is the mb trying to set the ram speed and it cant. with one ram stick if there no video see if someone has another stick of ddr4 see if the mb does not like it. also try posting the mb on top of the box that it came with to rule out a dead short. last issue check that the cpu is locked in and there no bent pins under it.