Well all of you nearly got that but
I

got the full description of the problem and its solution, so here it goes.
The ports of the PC are not fed power directly from the power supply, their power is however made available on board. This is done to be able to shut power to a port on the event of a short circuit.
SO the double beep you here before the six beeps signifies the detection of
that condition and serves as a notification for you that the motherboard is shutting ports down. That is why there is no video.
the following six beeps tell you that keyboard controller is not responding (Gate A20 error) and now you know why, well surly it will not respond because there is no power to it.
Intel has not documented it and that is very poor support.
I got that figured out when my Pc's USB port became broken and its wires touched its body (I was unaware of that). I came here to this forum But the answers were irrelevant
then I examined the motherboard and found the short circuit. So it may be a KVM's mouse output in the keyboard connector or a broken usb device attached or most likely a broken computer port like mine was.
😀 I got the meaning of six short beeps from phoenix bios codes and the

double beep's meaning from my experience.
so don't

go to a work shop just detach every thing on ports and look for the problem in case your (intel / phoenix bios) mother board throws this beep code on you.
happy fixing
bye.