CPU is running hotter at idle, after cleaning case, and updating bios.

[Protogon]

My CPU is suddenly running hotter at idle after I cleaned out the case, and updated the bios. It used to idle at 28-31C, now it's at 40-45C. Anyone know what might've happened? I read somewhere that it could be that the update changed the cpu voltage, but idk the stock voltage, so i cant confirm this. It's an Asus z87 mobo, i5-4670k at stock speed, GTX 960, the case has 3 120mm intake, and 2 140mm exhaust fans.

 

[Crixilian]

did you reapply the thermal paste?

 

[Protogon]

I didn't remove or really touch the heatsink, so I didnt think it was necessary. I removed the side panel, and blew off the dust from the fans and mobo with some compressed air.