Your CPU is rated to handle 3000mhz so 3200mhz is the highest I’d push it even though the mobo supports up to 3600mhz. Run DOCP but lower ram clock speed till its stable.

Do you mean you cleaned off the thermal paste off the gpu or cpu? Or did you actually mean thermal pads? There’s only thermal pastes for the cpu and the GPU has both. I’m guessing you mean CPU and yes it’s important as thermal paste helps heat transfer from the cpu to your cooler and without it, it’s going to overheat. I’d suggest not using your computer until you order a small tube and recommend Artic Silver for the brand. Look up a video on how to apply it and you should be good to go. If not, a pea size application on the CPU will do the trick.