I agree with Megahertz here. To test whether the motherboard is still alive you need to remove all drives, remove the memory, and try to boot up - the motherboard speaker should beep. If it does not, this means your motherboard is dead. If it does, you need to reset the BIOS. To do that you need to remove the CMOS battery and in addition you need to disconnect and reconnect the jumpers, but I think this last step is specific to your motherboard, you need to search on how to do that exactly.

Now, this kind of a hardware failure *CAN* be triggered by software - I had a case with a Dell All-in-One which gradually died after an update to Windows 10. Dell said they did not support Windows 10 on that machine and so the only possible solution was to find a specialty computer shop where someone could reprogram the BIOS chip on the motherboard. After that the machine works just fine (with Windows 8.1).

As to the last updates, I can confirm that on my two Windows 7 64 bit Ultimate all went well - the updates installed and both machines are working just fine. I did see this full screen notice of the support expiration, clicked "don't bother me" and that's that, no problems there. So I suspect this is an unfortunate coincidence, or indeed the BIOS got damaged during the restart.