Many different things can happen to a computer, but one of the worst and most annoying things to happen is the RAM becoming unseated. Something so small such as a bump to the tower can make the RAM become unseated. If the RAM has become unseated, the computer will lag and respond quite slowly. If a PC is responding slowly and lagging and it isn’t a Wifi connection, then it is most likely that there is a problem with the RAM. If I were to suspect a problem with the RAM, one of the first things that I would do is to run a Windows Diagnostics test on the memory to see if it is showing the right amount of RAM. For future references I would take note of the amount of memory. Then, taking apart my PC I would remove the memory module from the motherboard and then try and reboot the PC. After doing that, if an error shows up then I know that there is a problem with the RAM. My next step would be to try and replace the memory module and try rebooting the computer again to see if it starts with or without error. After making sure that the correct amount of memory is being shown, then I would take a precaution and use the computer a bit and open some browsers just to make sure that it is responding correctly to avoid further problems. I would also re run a Windows Diagnostics test just to be sure.
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