[SOLVED] New system build 1 long beep 3 short beep doesnt boot up

[Otosand]

I just build my new video editing system today, it powers up but no video, instead it gives me 1 long beep 3 short beep slight delay and 1 more short beep.
Not an expert system builder but not a total newbie either, this is the 4th system I build for myself and first time I have problem with a new build.

MB: Asus Prime Z390-A
CPU: i9 9900k
CPU Cooler/Fan: Corsair H100i Platinum RGB
Mem: Corsair DDR4 3000Mhz 16x4-64gb
GPU: Asus ROG Strix RTX 2070
PS: Corsair AX760 80+

According to beep code, it's a GPU error. So the first thing I did was unplug the video card and used the onboard video, no luck.
There are no extra MB standoffs installed, so no shorting there.
Next I unplugged everything to bare minimum only: MB, CPU+Cooler MEM, PS only, no luck
Maybe one of the memory is bad, so I setup every combinations possible with only 2 sticks installed, Memory# 1+2, 1+3, 1+4, 2+3, 2+4, 3+4, still no luck.
Since I don't have any compatible MB or CPU, I couldn't test them.
Any suggestions on what might be causing the problem?

 

[The Paladin]

take out ram and try to boot do you get the same code?

 

[Fix_that_Glitch]

Try backing off the screws of the cooler on the cpu. If they are screwed down too tight it will cause the cpu not to post up. It just happened to me when I put new thermal paste on my cpu. I had to really back off the screws a lot. Guess I got too enthused in tightening them.

 

[Otosand]

Thank you for the suggestions, I will try them when I get back.

 

[Otosand]

take out ram and try to boot do you get the same code?

I get 1 long beep 2 short beep, the beep sequence keep repeating none stop.

 

[Otosand]

Try backing off the screws of the cooler on the cpu. If they are screwed down too tight it will cause the cpu not to post up. It just happened to me when I put new thermal paste on my cpu. I had to really back off the screws a lot. Guess I got too enthused in tightening them.

I tried it, but still no luck

 

[Otosand]

Setup now out of the case, nothing connected but the bare essentials. still the same 1 long beep 3 short beep, slight delay one more short beep. I hope it's not the CPU or MB....

 

[Otosand]

Finally found the problem, it's because I have HDMI cable to monitor, once I burrowed a friend's monitor with Displayport, it posted just fine. I'd never guess......=(