Any program that is 64 bit will not even start if the OS is not 64 bit so it can’t be that.
Out of System Memory is likely you have graphics settings WAY too high, bad RAM in slots or GPU. It could also be Malware/Virus.
You should run a malware check and check memory on both your RAM and GPU RAM.
Check that you are getting enough power as well.
Run a disk check as well. If you haven’t reinstalled windows since it was released, it may be time to do so. Back up all your data and do a clean install. Everybody should do that every few years. It will give a massive performance boost and those junk files that build over time disappear. No program can clean as well as a reinstall.