Why Won’t My Lenovo T61 Think Pad Turn On?

Why has my Lenovo T61 Thinkpad suddenly decided not to powering up? This is the third think pad I’ve owned that has done this. One minute it’s working great next minute there’s no lights, power button won’t start it nor does it show that it’s charging when I attach the adapter/charger. All 3 did basically the same thing. I tried discharging any static by pressing the power button several times with the battery and adapter not attached. I tried removing the battery and replacing it. I tried using just the adapter. I tried using another battery and another adapter and nothing helps. I’ve tried myself to find answers but to no avail. I’m so hoping you folks can help me with this. I even tried plugging it into a wall socket versus a power strip. Nothing. I’m lost without my laptop. Hoping it’s something simple but if not please let me know and I will send it in to be repaired. Thanks so much