Download this: http://www.memtest.org/#downiso
Then Burn it into a Dvd/CD or make a bootable USB and boot from it and run the tests for like an hour or so... If there is a RAM issue... this should catch it...
But I do think it might be a virus... Try using task manager and see how much RAM ur PC is using or see which program is using the most amount of memory, Also turn off Windows Indexing service cause that usually takes up a lot of Memory
PC Specs: CPU: 7800X3D || GPU: Strix 4090 || RAM: 32GB DDR5 6000 || Main SSD: WD 2TB SN850







