Or "a system you see at the repair counter too often." The PSU was lightwieght then and after a few years is suspect. Try adding at least 200W to the new one. After that you have a known HDD seen with errors too many times.

Go get a Speccy report and the passing criteria is NO ERRORS in the HDD SMART VALUES. If you want folk to check for you, read https://www.piriform.com/docs/speccy/using-speccy/publishing-a-speccy-profile-to-the-web

Finally you see this machine and if the usual PSU and HDD don't fix it, it's usually an old motherboard. You replace those.

Finally the Asus R7 260 was known to cause lockups as well. Try the usual cleaning and fresh heatsink compound you read about on the web.