I am only after taking my computer apart to clean my cpu. I applied thermal paste all correctly using the card method. I cleaned old paste with alcohol I got from the computer shop and then used toilet roll to dry. This is my first PC that I built and I am so worried that I have damaged my CPU in someway. Can someone please help me!
You took your CPU out to clean it? WHY!?
It can be very likely that you killed it with electricity. If you weren't grounded/neutral when you touched it, your static electricity could have easily fryed the CPU.