I "installed" an h100iv2 last night. When I booted up the system the first time I looked into the bios to witness the awesome cooling, and then watched in horror as the tempature climbed until it hit 90 and turned off. I blame this on one thing, the extremely wobbly bracket on my MSI B350 MOBO. I installed the standoffs, but the stupid bracket pushed back alot. I figured that I could get it snug if I used some washers to get the hexagonal things flush with the board. What would be some safe washers to use for this purpose?