Question PC doesn’t boot after changing components


Jul 8, 2013
Hi guys, my PC was built sometime in March this year, it was working fine until I changed my CPU cooler from Cooler master Evo 212 to Corsair H100i platinum. After that, the PC simply won’t boot. I found out that I didn’t peel the 3M cover on H100i’s backplate, so I removed the cooler to do that. In the process, I reseated the CPU, cleaned up the thermal paste (I noticed a slight bit of thermal paste got onto the side of the CPU’s lid, touching the green portion. Tried to clean it off as much as I could, but some still present), and placed the cooler back on top of the cpu. But still no boot after that. :(

My components are (case is NZXT H500):
-Intel i5 8400
-Corsair Vengeance RGB 2x8GB 3000Mhz
-Asus Z390-F gaming
-RTX 2060 (removed due to artifacting)
-2x LL120 chassis fans

So the thing is, when the front panel’s power is pressed, Motherboard and chassis fan’s RGB switches on, ram’s RGB remains off, chassis fans do not spin. But after I fiddled with the flat battery on the motherboard (took it out and put it back in again), the fans start spinning. So basically right now, everything lights up except for the ram sticks.