Seeking Help for Random Computer Crashes and Instability

I've recently upgraded my computer with a new CPU, which also required switching out my motherboard and unfortunately reducing my RAM capacity. Ever since this upgrade, I've been facing some serious instability issues that often make my computer completely unusable. The symptoms include random crashes of programs, entire system freezes, and graphical glitches where sections of the screen sometimes become distorted. It's really frustrating!

Here are some specific issues I've been encountering:
- Programs randomly crash, freeze, or go blank without warning. Minimizing and maximizing helps sometimes, but it's not a fix.
- The whole system occasionally crashes, leading to a BSOD or just a blank screen.
- I've also experienced visual corruption, where parts of the display stretch oddly.
- Upon entering standby mode, the system often won't wake up unless I perform a full shutdown.

Strangely, I've noticed that playing more demanding games seems to make these issues less likely to occur, while they pop up more during regular desktop use or with lighter programs. It feels like as I use the computer over time, these issues worsen. Before the upgrade, everything was running smoothly, and now I'm at a loss as to what might be causing all this chaos.

I've tried multiple troubleshooting steps including reinstalling the OS, checking temperatures, testing power supply units, and swapping out graphics cards, but nothing seems to solve the problem. I still need to run some tests on the storage drives and the RAM to ensure they're functioning correctly, among other things.