Question PC won't boot, no screen, gigabyte Mobo death loop

Jun 21, 2019
Hey, I am using some of my brothers old parts which has has confirmed to be still working. The only thing that doesn't work is one of the two 8GB DDR4 ram sticks, and I have switched them out during tests and it makes no difference.

I am using:
GA-B150M-DS3H (DDR4) Motherboard
Intel i5-6500 LGA1151
Mushkin 16GB Blackline DDR4 PC4-19200 (2x8GB)
Ultra X4 Power supply (don't know wattage, haven't taken it out).
GTX 1660 TI

Okay. So I get stuck in this loop. First off, it does not turn on with the power button, so I probably got some of the f panel cords mixed up. A friend told me to try unplugging those and jump-starting it with a screwdriver. I did and it would start, run for 15 seconds without booting (screen wouldn't activate) and then shut off, then turn on again after 3 seconds. I have unplugged the gpu, other fans, f panel, pretty much everything except for the cpu fan and power. And yes, the cpu power is plugged in.
I honestly can't figure out why it won't stay boot. Thanks for help in advance. I'll be on all day tomorrow ready to answer questions and try out any solutions. I've tried to do some stuff that people with similar boards and problems but so far nothing worked.